wrong answer > - Use print statements or a debugger to see where exactly your
program does the wrong, your program gives the wrong answer > - Use print statements or a debugger to
see where exactly your
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You can use several words in query to find by all of them at the same time. In addition, if you are lucky search understands word forms and some synonyms. It supports search by title and author. Examples:
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Results
1.
debugger
Last visit:
14 years ago
Registered:
14 years ago
2.
How to ask for help in PM There was a blog today with a similar title, and although it was (I think, not really sure as I didn't get a good look) some kind of satire/joke blog, I wanted to post some serious advice about things I (don't) like to see when people are PMing me. However I decided that this wouldn't be in the spirit of the blog and decided to make a separate blog. And now that blog is deleted anyway.
While it's not a bad thing to write messages to more experienced users, most people who write me do things that make them very difficult to deal with. These are my opinions, but somewhy I feel that many reds will agree. Some things here feel silly to write because they are so obvious. But I'm only writing them because people regularly mess them up.
[cut]
$~$
####Use punctuation and spelling.
There are some [very simple rules](https://codeforces.me/blog/entry/82186#comment-689836) that make your messages infinitely more readable. I find it especially strange when many of these messagers call...
3.
[Tool] Graph Debugger Hi, CodeForces!
For the past 2 months I have been working on a Graph Debugging tool, which allows you to draw graphs like these with just **TWO** lines of code:
This is similar to print debugging (when you got a crash somewhere, so you repeatedly recompile the code with `cout << "penis\n";` to see where it failed), but instead it creates a window with the graph, which you can change however you want.
It is also a marginally better tool than graph editor from CSAcademy in my opinion, so I would love you guys to try it out.
This is not compatible with MacOS because Apple deprecated OpenGL (and even if it wasn't, it would've been kinda annoying to use)
## Building
First, build the code from the repo:
https://github.com/EnDeRGeaT/graph-debugger
If you write in Visual Studio (not Visual Studio Code), follow "For MSVC" part.
If you write in anything else, you probably should follow "For GCC/...
[Tool] Graph Debugger, ## Building First, build the code from the repo:
https://github.com/EnDeRGeaT/graph-debugger, -debugger?tab=readme-ov-file#issues) in the github repo., : https://github.com/EnDeRGeaT/graph-debugger If you write in Visual Studio
(not Visual Studio
4.
[Tutorial] The command line: how to read input from file without #ifdef and much more #### Introduction
Instead of algorithms and math, I'll be doing something completely different here.
There is something that has bothered me for a long time: people not understanding
the tools they use to participate in contests and thus failing to take real advantage
of them. And it all goes back to not understanding the command line.
Some of you might say, "well surely, the command line is something obsolete and you're
only clinging to it because you [insert ridiculous amateur-psychology here]?"
No! The command line is not obsolete, and unless competitive programming becomes
so mainstream that software vendors start writing professional-grade tools aimed
specifically at us, it won't be.
[cut]
$~$
What is the command line? Any of these:
As you can see, it comes in many background colors and fonts, but the basic idea
is always the same. It's a box you can type commands in, which it will ...
wrong answer > - Use print statements or a debugger to see where exactly your
program does the wrong, your program gives the wrong answer > - Use print statements or a debugger to
see where exactly your
5.
IOI 2018 impressions and conclusions Hi there!
As you all are aware, IOI 2018 is now over, and I felt the need to write a few lines about it, about my experience of it, and about my conclusions. I don't normally do that, but this was my last IOI and likely the end of my intense CP career.
So, the problems were absolutely great! Big up to the scientific committee. However, I'm sort of addicted to the codeblocks debugger which ruined the whole experience for me. As a matter of fact, the only reason for which codeblocks remained my primary editor was because its debugger was awesome and the only alternative of a better editor that I saw (better on the long run, including future real-life programming experience) would be vim which I knew is not even close to as friendly when it comes to user friendliness of debugging. I've also had competitions on a regular basis for 7 years and never had a time interval where I could say: well let's try something new cause we don't have anything useful to do (as I would always tell mys...
addicted to the codeblocks debugger which ruined the whole experience for me.
As a matter of fact, the, level, I genuinely want to advise you not to count on that debugger (there are
alternatives, like not, ! Big up to the scientific committee. However, I'm sort of addicted to the
codeblocksdebugger which
6.
How optimal is your CP setup? Click here and find it out! Recently I thought a lot about optimizing my setup. I don't think it is an important aspect of cp, as it barely affects the performance, but it is fun to think about nonetheless.
In this blog, you will be able to determine whether you have an optimal setup or not. I will list the criteria and points you get for satisfying each one of them. In the end, I do the breakdown for different point ranges.
I won't include things like **having a monitor** or **having an internet connection**, but I will be including basically everything else that comes to my mind. If you see something missing from the list, let me know in the comments, I will probably update my list then.
This blog is mainly made for laughs, but if you are new, you will probably learn something new, even though **it won't help you to increase your rating**.
### You can compile and run your code.
- $0$ points: I don't know how to run my code before submitting
- $10$ points: I compile my code b...
7.
Compilation and debugging tutorial In this tutorial I'm going to share some useful compilation and debugging tips. These tips can save you a ton of time debugging and make compilation and debugging convenient.
### Useful compilation flags
G++ has many useful warning flags such as
- `-Wall` enables all warnings. I highly recommend using this flags.
- `-Wextra` enables extra warnings.
- `-Wno-sign-conversion` silences sign conversion warnings for code like `x < vec.size()`
- `-Wshadow` enables shadowing warnings, so that if you define another variable with the same name in a local scope, you will get a warning.
Using these flags can save you time debugging silly mistakes like forgetting to return a value in a function or doing a comparison like `x < vec.size()-1` where `vec.size()-1` can underflow into `SIZE_MAX-1`.
#### Precompiled headers
You can use precompiled headers to substantially speed up the compilation of your code. Note that the precompiled header is only used if it is compiled with the ...
it just adds an extra piece of data in the executable that helps the debugger
map the executable file, -time, since it just adds an extra piece of data in the executable that helps
thedebugger map the, ~~~~~ compile a # Compiles a.cpp to a debug a # Runs a in the debugger with
input from a.in ~~~~~
8.
Sublime Text [FastOlympicCoding] — tools for competitive programming 
**Hello**, I would like to introduce the plugin FastOlympicCoding for Sublime Text.<br>
It provides several useful features for competitive programming.
[cut]
<br>
##### Test Manager<br>
- The main feature is test managing. You can effectively add, edit, and delete tests. See the screenshot above.
##### Debugger<br>
- Also for OSX, there is a debug functions.
##### Class Completions <br>
- The next feature is class completions.<br>
- Write chars as classes for a template substitution.
##### CppLint<br>
- C++ lint<br>
- Edit lint properties in settings.
, test generator, and interactor — then **checks them locally** and **uploads them to Polygon**.
→ **GitHub:** [https://github.com/7oSkaaa/polygon-problems-generator](https://github.com/7oSkaaa/polygon-problems-generator)
---
## The problem
Setting a proper problem for a contest takes a lot of time, even when you already know the idea:
- Writing a clean LaTeX statement in Polygon style
- Writing a bulletproof `testlib.h` validator (and validator tests)
- Choosing or writing the right checker
- Writing an accepted solution, a second ACC with a different approach, a TLE brute, and a WA solution
- Writing a generator with a complete FreeMarker script and real min/max tests
- Reviewing everythin...
the debugger. ``` idea → /generate-problem → originality → ./verify.sh →
python -m polyup, **Local first. Polygon second.** Do not use Polygon as the debugger.
10.
Debugging graphs with ease: experimental Visual Studio plugin Hi everyone!
I'd like to present you a prototype of Visual Studio plugin which was developed by a student from my university as a coursework. Yielding floor to her:
[GraphAlgorithmRenderer](https://marketplace.visualstudio.com/items?itemName=OlgaLupuleac.graphrenderer2019&ssr=false#overview) is an experimental Visual Studio extension for debugging and visualizing graph algorithms. It takes a description of graph nodes, edges and their properties, such as color and label, and renders a corresponding graph. The graph is refreshed automatically when you step in debugger. Graph config can be serialized to JSON and deserialized back.
[cut]
More explanations and detailed example can be found [here](https://github.com/olgalupuleac/GraphAlgorithmRenderer). Samp...
corresponding graph. The graph is refreshed automatically when you step in
debugger. Graph config can, debugger). We would be grateful if you help us to find out how to reproduce
this bug. 2. The UI is quite, debugger. Graph config can be serialized to JSON and deserialized back.
11.
C++ and VSCode setup on macOS ### Problem to be addressed
On Linux it is pretty straightforward to set up the debugger for C++ on VSCode. The workflow is:
- Write your code
- Go to the [Run and Debug] VSCode section
- Click on run active file or something similar
- Debug your code
On macOS you will run into a lot of silly problems, such as:
- Can't find `#include<bits/stdc++.h>`
- Installed g++ and got the debugger running, buck can't write input to `std::cin` in the integrated terminal, because it says
~~~~~
Build finished successfully.
* Terminal will be reused by tasks, press any key to close it.
~~~~~
and then closes the terminal, making it impossible to write to `std::cin`.
After some time browsing the internet I found the solution for all those problems and got my setup working just like on linux.
### Solution
Let's brake the solution step by step, from a almost brand new macOS.
1. [Install Homebrew](https://brew.sh)
2. Install g++ (`brew install gcc`)
3. Down...
generated by Debugger." } ], "version": "2.0.0" } ~~~~~, have to compile and then run the debugger every single time, which is annoying
and error prone. Also, ### Problem to be addressed On Linux it is pretty straightforward to set up the
debugger for C, - Installed g++ and got the debugger running, buck can't write input to
`std::cin` in the
12.
Editorial [GYM] 2018 BACS Contest replay [problem:101864A]
Setter: [user:ISwearItIsMyLastContest,2018-08-10]
Alternate Writer: [user:prophet_ov_darkness,2018-08-10], [user:s_h_shahin,2018-08-10]
<spoiler summary="Editorial">
This problem actually reflect the [josephus problem](https://en.wikipedia.org/wiki/Josephus_problem).
The main part of this problem is to find Number of possible Y such that **josephus(Y,2) = X** .
After finding this rest part is obvious calculation.
Let’s see first few values of josephus(i,2): 1 1 3 1 3 5 7 1 3 5 7 9 11 13 15
We can see that there is a nice pattern here. **josephus(n,2)** is an increasing odd sequence that restarts with **josephus(n,2) = 1** whenever the index **n** is a power of 2.
First we will find minimum value of p such that **josephus(p,2) = X**. we can do this in **O(log n)** , because for every **q>0** **josephus(2^q-1,2) = 2q^-1** and **josephus(2^q,2) = 1**. So we can run loop through q >= 0 and find highest value of **q** such that **josephus(2...
;} #define debug(args...) {dbg,args; cerr<debugger{ template, struct debugger{ template debugger& operator , (const T& v){ cerr<
Tutorial of 2018 BACS Contest Replay
13.
Let's Settle This Let's turn the controversy up to 11 (not in binary). Feel free to post some more polls in the comments if you want to
**What is this data structure called?**
Disjoint Set Union
Union-Find
**How do you indent?**
2 Spaces
3 spaces
4 Spaces
Tabs
No indentation (you need help)
**Best language for CP?**
C
C++
Python
Java
**What type of variable do you prefer?**
Local
Global
**How do you bfs/dfs?**
Deque
Recursion
Deque for bfs, recursion for dfs
Some from the comments:
**(C/C++ only) How do you I/O?**
Cin/cout
Printf/scanf
Custom superfast io
**What range do you use?**
in...
14.
precompiling stdc++.h ai generated markdown:
Here are the steps to speed up C++ compilation time by precompiling the "bits/stdc++.h" header on a Windows machine and modifying CodeBlocks' settings to use them:
1. Delete the Mingw compiler from CodeBlocks and remove Mingw from PATH if it is present.
2. Download the latest version of [msys2](https://github.com/msys2/msys2-installer/releases/download/).
3. Open the MSYS2 shell from the start menu and execute the following commands:
- Update the package database by running `pacman -Sy pacman`.
- Update the package database and core system packages with `pacman -Syu`.
- Update the remaining packages with `pacman -Su`.
- For a 32-bit system, install the 32-bit toolchain by running `pacman -S mingw-w64-i686-toolchain`. For a 64-bit system, install the 64-bit toolchain with `pacman -S mingw-w64-x86_64-toolchain`.
4. Open the Command Prompt as an administrator, navigate to the C: drive, and execute `mklink /D MingGW C:\msys64\mingw64`.
...
++17` or `-std=c++20` ( **important** ). 12. In CodeBlocks, go to "Debugger
Settings Default, 12. In CodeBlocks, go to "Debugger Settings Default," "Executable path," and
paste `C:\msys64
15.
Debugging in C++ Hi everyone.
This is my template for debugging in C++. I was inspired by Tourist's [source code](https://codeforces.me/contest/1110/submission/49588803) and modified it to my style. Here is it:
<spoiler summary="Template">
~~~~~
#include <bits/stdc++.h>
using namespace std;
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.seco...
`for (auto i: a)`. So the debugger won't work with collection types like
`std::queue` or `std::stack, the debugger won't work with collection types like `std::queue` or
`std::stack`.
16.
C++ Debugger Hello codeforces!
This is the debugging header i use in C++ wich i got from [user:Tourist,2024-01-07] and modified it a bit
<spoiler summary="Debug.h">
```c++
#include <bits/stdc++.h>
using namespace std;
void __print(int x)
{
cerr << x;
}
void __print(long x)
{
cerr << x;
}
void __print(long long x) {
cerr << x;
}
void __print(unsigned x) {
cerr << x;
}
void __print(unsigned long x) {
cerr << x;
}
void __print(unsigned long long x) {
cerr << x;
}
void __print(float x) {
cerr << x;
}
void __print(double x) {
cerr << x;
}
void __print(long double x) {
cerr << x;
}
void __print(char x) {
cerr << '\'' << x << '\'';
}
void __print(const char* x) {
cerr << '\"' << x << '\"';
}
void __print(const string& x) {
cerr << '\"' << x << '\"';
}
void __print(bool x) {
cerr << (x ? "true" : "false");
}
template<typename T, typename V>
void __print(const pair<T, V>& x) {
cerr << '{';
__print(x.first);
cerr << ',';
__print(x.s...
C++ Debugger, not complete but it can show how you define the debugger How to use:
------------------ you, the debugger will print them, The code is not complete but it can show how you define the debugger
17.
[Tutorial] Setting up Windows C++ environment — Microsoft edition Hello. This is kind of continuation of this post https://codeforces.me/blog/entry/102287. In this tutorial I'll try to explain how to write and compile C++ code on Windows, using tools provided by (mostly) Microsoft. I'm going to use latest versions.
Terminal
========
First of all, let's install [Windows Terminal](https://www.microsoft.com/store/productId/9N0DX20HK701) and [MS PowerShell](https://www.microsoft.com/store/productId/9MZ1SNWT0N5D). Standart windows command line is just not usable. Let's also install [winget](https://www.microsoft.com/store/productId/9NBLGGH4NNS1) — this is a package manager similar to, for example, homebrew. Maybe chocolatey is better but, again, this one is developed by Microsoft.
Of course Microsoft Store isn't mandatory, you can use any other source for these packages.
I'd also suggest to try [starship](https://starship.rs/) command prompt — very useful tool, supports powershell as well.
Compilers and tools
================...
write about visual debugger (https://github.com/daveleroy/sublime_debugger)
but I actually almost don't, That's it I guess? My initial idea was to also write about visual debugger
(https://github.com
18.
CodeJam does not have filter by country feature — annoying, what to do? CodeJam is a great platform with interesting problems. But I think I'm not the only one who is annoyed because you can not filter all the participants from your country. That feature can help you to find your friends who are participating too, but you can find them if you know their username beforehand.
I have found a work-around solution for that.
- Copy this
<spoiler summary="BLAHBLAH">
javascript:const country=prompt().toLowerCase(),button=document.querySelector(".ranking-table-pagination-chevron-right").parentElement.parentElement,getHash=()=>{return Array.from(document.getElementsByClassName("penalty-time")).reduce((e,t)=>e+=t.innerText,"")};let answer=[];const doCurPage=()=>{const e=Array.from(document.getElementsByTagName("img")).filter(e=>(e.src||"").toLowerCase().includes(country)).map(e=>e.parentElement.innerText);console.log(e),answer=[...new Set([...answer,...e])],console.clear(),console.log(answer)};let hash=getHash();const hashChanges=()=>new Promise(e=>{cons...
at some point and don't want to continue, type `debugger` in the console, and
freely explore the, - If you are happy at some point and don't want to continue, type `debugger` in
the console, and
19.
A sample example for debugging code for newbs (like me) This is something which I was happy to achieve on my own for [problem:2004D]. I quickly achieved the greedy binary search, but I had few un-intended bugs (ideally would've saved time if I did a code review instead of debugging, but as a trade-off you do get a confidence that it will get resolved after debugging)
**Here is the why this blog is for you:**
- You are newb like me.
- You get frustrated when your code randomly gets WA and you don't know what the edge case/bug is there in your code.
**Here is probably why this blog is not for you:**
- You are too good (please ignore, although, you can improvements are welcome!)
- You probably know what to do, but just don't feel like debugging. (well, that's the only way I know which will work for sure for now)
**Thing which helped the most:**
[Debug template](https://codeforces.me/blog/entry/125435) — by [user:Anshul_Johri,2024-08-25]
**TL;DR of the debugger**
1. Write the most correct version you can think o...
and not improving my debugger code), **TL;DR of the debugger**
20.
Reusable modular integer for C++ (with static/dynamic moduli) <spoiler summary="A little bit about myself">
This is my first blog post on CF, and is probably a good starting topic for someone of my rating. Technically I'm not a CS, but an engineer who worked professionally as a software developer. CP was uncharted territory to me until recently, though now I find myself studying algorithms and working to improve my math skills so I can have fun solving difficult problems. :)
</spoiler>
So here's what I present: a structure for modular arithmetic operations which is short, reusable across static and dynamic moduli, supports 64-bit moduli and is as efficient as performing the operations manually. It requires the C++17 standard or newer.
### Motivation
For the most part, there's obviously nothing novel about this idea: it was inspired by other blog posts ([63903](https://codeforces.me/blog/entry/63903), [23365](https://codeforces.me/blog/entry/23365)), as well as by various submissions to CF problems. On the other hand, I haven't come a...
the debugger output. You can customize the summary string for a specific type
by issuing the, /7fbe826f2016e66bf41216640507fade6769e3ac.png) In order to address this issue,
we need to customize thedebugger. I will now, In order to address this issue, we need to customize the debugger. I will now
show you how this can
21.
SNWS 2015 Round 4 — screencast Some time ago in russian discussion of SNWS 2015 [user:ballon,2015-01-30] said that I should start recording screencasts of my participation in contests. It sounded like a joke for me, and I don't think that it is interesting for a large number of people; but still I decided to try something new and record one of contests, even if I am not going to do it on a regular basis in future. At least now I can save a lot of time while answering questions like "How are you coding", "do you use debugger", "do you prefer CodeBlocks or Visual Studio" and so on.
Below you can see a screencast of my participation in SNWS 2015 Round 4. Problem statements are in russian. There are nothing interesting after 47th minute, when all tasks are done — only refreshing standings from time to time.
_P.S. For those of you who are not familiar with SNWS/SNSS — SnarkNews winter series/SnarkNews summer series is a contest series held every year; it consists of 5 rounds with virtual participation, ...
I can save a lot of time while answering questions like "How are you coding",
"do you usedebugger
22.
Help in Dynamic Connectivity problem Hello Codeforces! <br>
problem link: [Connect and Disconnect](https://codeforces.me/gym/100551/problem/A)<br>
my buggy solution:
<spoiler summary="Spoiler">
~~~~~
/**
* “Experience is the name everyone gives to their mistakes.” – Oscar Wilde
*
* author : prodipdatta7
* created : Thursday 26-March, 2020 08:55:24 AM
**/
//#include <bits/stdc++.h>
#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <stack>
#include <queue>
#include <deque>
#include <iterator>
#include <bitset>
#include <assert.h>
#include <new>
#include <sstream>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
// #pragma GCC optimize("Ofast")
// #pragma GCC target("avx,avx2,fma")
// #pragma GCC optimize("unroll-loops")
using namespace std ;
using na...
/*###############-> Debugger <-###############*/
23.
How to learn the art of testing solutions Greetings Everyone,
It's just one of those days when I feel too lazy to solve any problems on Codeforces but don't feeling like doing anything else either.
In the past few contests I have been annoyed by bugs which result in WA/TLE etc and wanted to know is there any systematic approach to problems testing in competitive programming which can be applied to remove bugs, that too in an intense pressure situations (like ICPC). Because most of the time while I am testing some bug in my implementation, I throw random testcases at the solution and expect it to fail and incase it does I consider myself really lucky. I would like to ask all the experienced guys about any tips/tricks/tools for testing the solutions which they would like to share.
So far after messaging some people the valuable tips that I have received include
(text in italics are excerpts of actual messages received)
1) **Reading the problem statement carefully**
(not so valuable but still important :)
2) **...
4) **Learn to use gdb or any debugger**
24.
10 Types of Contestants You'll Meet on Codeforces 1. **The Speed Demon**: Solves the first problems in 3-4 minutes, then disappears.
2. **The Debugger**: Spends half the contest fixing one off-by-one error.
3. **The Code Golfer**: Writes solutions in a single unreadable line of code.
4. **The Rating Enthusiast**: Cries or celebrates for hours depending on the delta.5.
5. **The Strategist**: Spends 90% of the contest figuring out which problem to solve.
6. **The Meme Lord**: Writes problem comments or variable names as jokes.
7. **The Optimizer**: Finds a $O(\log n)$ solution for a $O(n)$ problem unnecessarily.
8. **The Tester**: Runs stress tests even for the simplest problems.
9. **The Philosopher**: Comments on the beauty (or lack thereof) of a problem's logic.
10. **The Perfectionist**: Refuses to submit until every edge case is covered.
11. **The Hacker** : Spends 30% of the contest solving the easy problems and the remaining 70% stress-testing others' solutions.
Which one are you, or do yo...
2. **The Debugger**: Spends half the contest fixing one off-by-one error., Debugger**: Spends half the contest fixing one off-by-one error. 3. **The Code
Golfer**: Writes
25.
Unknown Language Round #4 <p>The round is over; I hope you enjoyed it. <a href="http://codeforces.me/blog/entry/3226">Here</a> is the editorial.</p>
<br />
<p>The language of this round is Befunge, a lovely two-dimensional esoteric language. It's quite neat and convenient, especially for an esoteric language. Thus, for example, "A+B" problem, where A and B are given in separate lines, can be solved like this:</p>
<pre>&&+.@</pre>
<p>To learn the language you can read <a href="http://catseye.tc/projects/befunge93/">the original documentation</a> (the rumor is that it is broken in some browsers), examples of programs at <a href="http://rosettacode.org/wiki/Befunge">Rosetta Code</a> and <a href="http://progopedia.com/language/befunge/">Progopedia article</a> with annotated examples.</p>
<p>Our testing system uses <a href="https://github.com/programble/befungee">befungee</a> interpreter, which implements Befunge-93 dialect. To run the interpreter, one needs to have Python installed (version 2.6...
<Befunge program name> command. Note the built-in debugger (run with --debug, ;Befunge program name> command. Note the built-in debugger (run with --debug
--delay=100
Announcement of Unknown Language Round 4
26.
A Browser-Based C++ Compiler & Visual Debugger Hi everyone,
I recently built a project called C-Debugger – a C++ compiler and visual debugger that runs directly in the browser. It supports basic C++ features like variable declarations, arithmetic operations, control structures (like if-else, for, while, do-while), and simple output with cout. The idea is to help beginners understand how their code executes, step-by-step, without needing to install any compiler or set up their system.
As someone who struggled with understanding code flow and logic during the early days of learning C++, I wanted to create something that makes it easier to learn by visualizing what’s actually happening behind the scenes. Right now, the debugger supports only basic features, but I’m hoping to expand it over time.
I’d love to get feedback from the Codeforces community – whether it’s feature suggestions, bug reports, or even contributions to the GitHub repo. If you’re interested, the project is open-source here:
GitHub: https://github.com/Deba69/...
A Browser-Based C++ Compiler & Visual Debugger, happening behind the scenes. Right now, the debugger supports only basic
features, but I’m hoping to, Hi everyone, I recently built a project called C-Debugger – a C++ compiler and
visualdebugger
27.
Competitive Programming Assistant: all in one bash script Hello Codeforces!
I would like to introduce a command-line tool I've been working on to make competitive programming more streamlined and efficient: Competitive-Programming-Assistant (CPA). Natively can install in linux and macOS and can install in windows by WSL.
Installation
------------------
**Prerequisites**
Before installing, make sure you have the following installed on your system:
- g++ and gcc
- git and curl
- jq (Command-line JSON processor)
- nc (netcat, used to listen to Competitive Companion)
- Competitive Companion Extension installed in your browser.
**Command**
``bash -c "$(curl -fsSL https://raw.githubusercontent.com/sourav739397/Competitive-Programming-Assistant/main/install.sh)"``
Key Features
------------
- Automated Parsing (via Competitive Companion): With a single click in your browser, CPA parses the problem name, time limit, memory limit, and sample tests. It automatically creates the source file and opens it in your editor (defaul...
(-d) with sanitizers enabled to catch bounds errors and memory leaks and also a
debugger., debugger. - Advanced Output Comparison
([testlib.h](https://codeforces.me/testlib) Support
28.
I Ported FastOlympicCoding to VSCode! Welcome to ⚡VSCode FastOlympicCoding!⚡
------------------
Hello everyone! Some of you may know the [FastOlympicCoding](https://github.com/Jatana/FastOlympicCoding) plugin for Sublime Text, but I took the time to create my version of it in VSCode!
Most things are kept the same, such as the keybindings and the general theme of the UI. Other features differ due to the fundamental asynchronous design and various little things.
Some features are cut out because I wanted this extension to **integrate** with other extensions, instead of being "the extension that does it all". For example, the original plugin had debugger support _(even though it was only for OSX)_, and there are many good debugging extensions on VSCode, so it does not make sense for me to provide a crappier debugging experience.
#### _So, if you use VSCode, definitely give this a try!_
The extension is not co...
example, the original plugin had debugger support _(even though it was only
for OSX)_, and there are many, , instead of being "the extension that does it all". For example, the original
plugin haddebugger
29.
How I Solved C++ Compiler Issues that Bothered Me For Months My very first post is going to be merely a rant about what I went through with a compiler installation error, but I do this just for the record and to never forget this milestone.
Today I installed VSCode to embark on my USACO journey. However, my debugger would not work. It was a GDB debugger.
VSCode could not find the GDB debugger.
I discovered that the folders and directories were all jumbled up. There were repetitive files in different directories. one of them had a gdb.exe file and the other did not.
The problem dates back to when I took my first programming class in college.
It was an asynchronous course where the main material of which was just a learning website.
The course required me to install this very specific IDE, which was CLion. And then it required me to install the MinGW compiler(or a package that had a compiler & debugger & other things within it). This was where all the problems broke out.
The MinGW installer would not work. It shot out an error...
Solving using this compiler and debugger I fixed., installed VSCode to embark on my USACO journey. However, my debugger would not
work. It was a GDBdebugger, to install the MinGW compiler(or a package that had a compiler & debugger &
other things within it, without using a debugger., The PROBLEM was that I could not use the debugger., Today I installed VSCode to embark on my USACO journey. However, my debugger
would not work. It was, VSCode could not find the GDB debugger.
30.
Do You Use a Debugger? Context: On a recent contest I got Java'ed so I decided that I would permanently switch to C++. That being said, I found that generally C++ debuggers were less effective than the one I'm currently using for Java (this is my personal opinion, feel free to disagree). Fast forward to today, I was complaining on Discord that I couldn't get my debugger to work properly and in response, my friend told me that debuggers are "stupid" and that "nobody uses a debugger." This started a mini-debate about debuggers and who uses them which brings me back to my original question: do you use a debugger? Please let me know in the comments.
Have a great day!
Do You Use a Debugger?, complaining on Discord that I couldn't get my debugger to work properly and in
response, my friend told
31.
I made a modern Dev-C++ alternative for competitive programming Hi Codeforces,
When I started learning C++ as a first-year student, I bounced between two options. VS Code looked great, but I spent more time installing MinGW and fixing configs than writing code, just to get <bits/stdc++.h> to work. Every time I switched machines, like the PCs in the lab or at a contest, I had to do it all over again. And it wasn't just me: a lot of my classmates got stuck at the same step before writing a single line of code. Dev-C++ just worked, but it felt stuck in the past, and there was nothing I could change about it.
I'm also the kind of person who likes making my coding space feel like mine. So at some point I thought: why not build the IDE I actually want to use, one that my classmates could just install and start coding with?
That became Sameko Dev C++. It's free and open source, and the goal is simple: as easy as Dev-C++, but modern and yours.
- GCC 16 comes bundled on Win...
Companion support to pull tests from Codeforces / AtCoder. - A GDB debugger
that shows vector, map, debugger that shows vector, map, set... in a readable way, plus an "Auto dry
run" that steps through your
32.
Use debugger or print jfjd? Hi Codeforces!
<spoiler summary ="Does this only happens to me?">
</spoiler>
What are your thoughts about using a debugger?
- It's best to use it, I use it!
- I feel more comfortable debugging manually
- I think it's worst for competitive programming
<spoiler summary = "
To the voters:">
I hope that the ones who voted before making this edit will check the blog again ( **fingers crossed** )
What's your rating?
- GM or above
- Expert or above
- Last, but not least, specialist or below
</spoiler>
Thanks for reading and remember always to use dark theme editors :)
Use debugger or print jfjd?, What are your thoughts about using a debugger?
33.
My extension for running/testing solutions in VS Code Hi,
I've been using and maintaining this VS Code extension for over two years and it's been extremely useful
for both CP and random programming projects. So I decided to share it here, hoping
some of you will find it useful too.
The extension is called "Build and Run" but it can do a bit more than that:
- Compiling the code with a custom command
- Running the code with the given (multiple) inputs specified as comments in the same source file
- Comparing the program's outputs with expected outputs specified as comments
- Formatting the code with a custom formatter
- Building and running the code under the debugger
Unfortunately, interactive input or debugging isn't supported
(and I don't have plans to implement that -- stick to the normal terminal for that).
Configuration is a bit involved but I think README contains a good starting point.
The whole idea of the extension is to be fully customisable to have fun tuning it for yourself :)
[Download link](https://...
code under the debugger
34.
Exposing a cheater, making his way to Candidate master without getting caught Hey Codeforces Community,
There's a user, [user:chayankumawat2004,2024-06-09], who seems to be cheating his way to Candidate Master rank. He uses gibberish language in his codes to prevent it from plagiarism, for example he made a debugger function, which is nothing but a bfs, with no node pushed, he also comments out templates, and sometimes, add gibberish code in main function even after printing the answer which is obviously cheating, and he is doing this to avoid plagiarism.
When i confronted him, and asked for explanations, he couldn't answer and just tried to divert me from this topic.
He has been performing really well in recent contest, even today, he solved A-D, with the help of cheating, and gave almost master level performance
Here are some examples of his questionable submissions:
[submission:258916350]
[submission:262776253]
[submission:264959663]
Despite his unethical behavior, he's still progressing towards CM and achieving good ranks. I am not jeal...
made a debugger function, which is nothing but a bfs, with no node pushed, he
also comments out, plagiarism, for example he made a debugger function, which is nothing but a
bfs, with no node
35.
Could someone explain the behavior of this program to me? Hello,
I was implementing a simple Trie when I found a behavior that I didn't understand. I followed the program using a debugger, the issue seems to be in the `insert` function. I explained the issue in code comments.
~~~~~
struct Trie{
struct Node{
int id, nxt[26];
Node(int id) : id(id)
{
memset(nxt, -1, sizeof(nxt));
}
};
vector<Node> v;
vector<bool> leaf;
void init()
{
v.clear();
leaf.clear();
addNode();
}
int addNode()
{
v.push_back(v.size());
leaf.push_back(false);
return (int)(v.size()) - 1;
}
int getSizeMinusOne()
{
return (int)(v.size()) - 1;
}
void insert(const string &s)
{
int cur = 0;
for (char c : s)
{
c -= 'a';
if (v[cur].nxt[c] == -1)
{
// Note I only use one of the following NOT both at the ...
followed the program using a debugger, the issue seems to be in the `insert`
function. I explained the, program using a debugger, the issue seems to be in the `insert` function. I
explained the issue in
36.
Clang or GCC and why I moved to the first one UPD: Thanks to [user:jalsol,2021-09-17] and [user:imachug,2021-09-17] for solution to this problem.
And yes, it was my problem, not GCC's one) Moreover, it was because `#pragma GCC optimize("Ofast")` and it's not a big question why it doesn't work in Clang :)
Problem:
-------
As you may know, usually on competitions (especially when you're coding on linux OS) GCC compiler is being used. And GCC is utterly the most popular one, I can't argue on this point. What about Clang — it's commonly known as MacOS compiler because Apple with zealous gruffness built it in the all of their PC products.
So a few weeks ago I switched OS from Ubuntu to Deepin because according to some circumstances I thought that my OS had been crashing) and btw I was right and btw Deepin is much user friendly than Ubuntu. So I changed OS then installed Clion and closed my PC, and for a week or so I used only my mac laptop, because it was just improbable to debug in such a fword compiler. Like ok, ...
interested in using a debugger, move to Clang. Good luck on contest. Bye! . I have kept the design principle of optimal screen utilization while being jam packed with functionality. The design has been re-imagined to match the experience of Visual Studio Code. And, here are some of the new major tools added:
- **Debugging testcases directly in real-time!** You do not have to launch the debugger and send inputs manually anymore
- Interactive testcase support for both judging and stress testing
- Time and memory limit
There are too many hidden changes for me to write here, but the end goal has always been to **provide a native VSCode experience for competitive programming.**
**The extension is available for download at [Visual Studio Marketplace](https://marketplace.visualstudio.com/items?itemNa...
- **Debugging testcases directly in real-time!** You do not have to launch the
debugger and send, : - **Debugging testcases directly in real-time!** You do not have to launch the
debugger and send
38.
Getting Segmentation Fault on my Machine, AC on Codeforces Hello,
I was trying to solve [problem:1117D] using Matrix Exponentiation. I'm trying to use an implementation (It was moriss821028's if I recall correctly) for Matrix Power since it's much faster than mine. I'm using 2 transformation matrices and multiply them to get the final transformation matrix named `transform` and then raise it to the power of `n`.
This submission: [submission:58207232] gets AC, while on my machine it gives segmentation fault on `line: 108`, the line where I raise the `transform` matrix to the power of `n`. Following it with the debugger, it doesn't enter the `operator ^` function at all, it stops on the definition line and halts.
Reducing the dimensions of the array `v` to `180 x 180` seems to fix the issue locally but the code doesn't seem to take that much memory. Idk if this is related to a memory leak or what.
My IDE is CLion, the compiler is MinGW version 5.0, my CMake version is 3.13.2, and I'm using C++ 14.
It prints exit message `...
raise the `transform` matrix to the power of `n`. Following it with the
debugger, it doesn't enter the, the debugger, it doesn't enter the `operator ^` function at all, it stops on
the definition line and
39.
Best IDEs for C++ in Mac When I started competitive programming, I used CodeBlocks in Windows, because it had an easy to use debugger, and it achieved everything I needed for CP easily.
After I transitioned to a Mac and tried CodeBlocks there, I realized it wasn´t design to run on a Mac and it was running incorrectly. So I found c9.io, a free online IDE. This was great and I really liked using it. But now this place is closing and I am going to need a new IDE to use for Competitive programming and I am not quite sure which one would be better for me, and I think here people with experience with other IDEs could really help me get to a good one.
I use debugging a lot in CP, and I really like user friendly IDEs ( I tried VIM and i did not get it at all ).
Which one would you reccomend for me? I would appreciate the help very much. Thanks!
debugger, and it achieved everything I needed for CP easily.
40.
Code works on Vscode but not Codeforces The code below works for me in VScode for [problem:1548A], but it doesn't work in codeforces. The output is completely different. Does anyone have any idea on how to get it working again?
~~~~~
// ========== HEADER ==========
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#include <bits/stdc++.h>
using namespace std;
// ========== HEADER ==========
// ========== SHORTCUTS ==========
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
typedef vector<int> vi;
typedef vector<string> vs;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
template<class T> using pq = priority_queue<T>;
template<class T> using pqg = priority_queue<T, vector<T>, greater<T>>;
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (...
<< "[" << #x << "] = ["; _print(x) #else #define dbg(x...) #endif // ==========
DEBUGGER ==========, ========== // ========== DEBUGGER ========== void __print(int x) {cerr << x;}
void __print(long x) {cerr << x, // ========== DEBUGGER ========== void __print(int x) {cerr << x;} void
__print(long x) {cerr
41.
C++ errors debugger I am attempting to make my debugging tool better for C++. I currently have a script that runs with the following flags:
`-Wall -Wextra -O2 -D_GLIBCXX_DEBUG -D_GLIBCXX_DEBUG_PEDANTIC`. When I run my code with these flags, one of the errors I sometimes receive is that I attempted to a subscript container with an out-of-bounds index. While this is very useful, if my code is long, I am not sure which line and/or container this refers to. Is there any way to make this more specific (like how Java IDE tells the specific line and object that caused the error).
The following is an example:
~~~~~
Error: attempt to subscript container with out-of-bounds index 8, but
container only holds 8 elements.
Objects involved in the operation:
sequence "this" @ 0x0061FE40 {
type = std::__debug::vector<int, std::allocator<int> >;
}
~~~~~
C++ errors debugger
42.
Invitation to Apeireon Hacking Challenge Hey Codeforces!
Greetings from NJACK, the Computer Science Club of IIT Patna,
We feel excited to announce our very first edition of Apeireon , the annual coding fest of the Department of Computer Science and
Engineering, IIT Patna. The fest will be packed with a plethora of fun events for all our dear "logicians".
Introducing this time, Hacking Challenge, an event that requires you to think about the edge cases for the problems.
The event is analogous to the process of hacking where we have to find loopholes in a built system.
Here, you will be given a problem and its partially accepted solution (a code which seems to be correct but fails on some of the test cases), and you as ‘the debugger’ have to find an ‘edge’ test case where it fails.
The problems have been prepared by [user:eThAnE,2020-03-27], [user:MinorMiracle,2020-03-27], [user:Redemptioner,2020-03-27] and [user:ElusiveDream,2020-03-27].
1st Prize : 5000 INR
2nd Prize: 3000 INR
3rd Prize: 2000 INR
Ranks...
‘the debugger’ have to find an ‘edge’ test case where it fails. The problems
have been prepared by, ), and you as ‘the debugger’ have to find an ‘edge’ test case where it fails.
The problems have
43.
Linux and QtCreator <p>I think the best C++ IDE on Linux is QtCreator. It looks cute and only in this IDE I can debug STL containers and algos without going to their .h files :D</p><p>But sometimes it happens(but not sometimes, often), that you can't cin of scanf in this IDE(or debugger shows you an error ><). You can solve these problems by making these easy steps :)</p><p>1. If cin of scanf doesn't work</p><p>Tools -> options -> Environment -> System-> Terminal(change to xterm -e)</p><p>External Terminal : change to xterm -e -geom %Wx%H+%x+%y -e vi %f +%l +"normal %c|"</p><div>In left panel(Projects -> Run settings -> click on "Run in Terminal"</div><div><br /></div><div>2. If debugger shows you an error, type in Terminal:</div><div>sudo echo 0 > /proc/sys/kernel/yama/ptrace_scope</div><div><br /></div><div>Good luck :)</div><p</p>
sometimes, often), that you can't cin of scanf in this IDE(or debugger shows
you an error ><, 2. If debugger shows you an error, type in Terminal:, debugger shows you an error ><). You can solve these problems by making these
easy steps :)
44.
Google Code Jam Interactive problem setup on Windows Hello
I'm stuck and unable to get the setup for the interactive problems on GCJ to work on my computer (Windows 10). Specifically, the interactive judge and the python debugger that the Google Code Jam team provides. I am a relative newbie, I find the interactive problems interesting, and have been able to solve the past GCJ interactive probs, but haven't been able to code and test them.
I know I won't advance to Round 2, but I want to be able to at least enjoy the Round 1, if an interactive problem comes up (coz I can't solve the others anyway! -_-)
The process seems tedious as I do not know Python.
I have searched this on Youtube. I know Errichto has a video on solving Interactive problems, but it doesn't go through the setup (I am able to solve the problem, the technical setup is the issue). Moreover, he works on on Linux, it's different from Windows i guess.
Has anyone managed to get it working on Windows?
If yes, I'd highly appreciate your help!
Thank you!
computer (Windows 10). Specifically, the interactive judge and the python
debugger that the Google Code
45.
Какой Java editor или IDE используете Вы? <p>Добрый день, </p><div><br></div><div>Меня заинтересовал один очень интересный вопрос: Какой java editor или IDE удобнее использовать для решения олимпиадных задач по "спортивному программированию".<br></div><div>Я например, использую NetBeans IDE 7.0. У него есть autocomplete, systax hilighting, java debugger. Но мне не нравиться создавать для каждой задачи отдельный проект. В одном проекте создавать классы для каждой задачи тоже не удобно. Создал эту тему, чтобы java кодеры поделились своим опытом использования инструмента для написания задач, например от CodeForces, TopCoder, CodeChef.</div><div>Спасибо!</div><p></p>
hilighting, java debugger. Но мне не нравиться создавать для каждой задачи
отдельный проект. В одном, debugger. Но мне не нравиться создавать для каждой задачи отдельный проект. В
одном проекте создавать
46.
What is your competitive Programming setup for contests? Which IDE/Editor do you use and what do you like about it? How do you test for sample tests of the problem fast? Do you use terminal during contest? Also how do you debug your code during contest? Do you use IDE Debugger or debug manually?
you use IDE Debugger or debug manually?
47.
Display a dynamic array of structs in the MVS debugger How to see the content of dynamic array of objects in Microsoft Visual Studio (2010) on the debug watch window. [For example.](http://ideone.com/y6I8Pi)
Display a dynamic array of structs in the MVS debugger
48.
Need advice for Debugging in Java editor This is specifically for IntelliJ as it’s highly recommended for Java but the debugger is not as I want it to be.
The functionality seems pretty good but debugging 2D arrays is a pain as I can’t get a complete view of the array at once as opposed to an Eclipse editor.
So can anyone suggest a workaround or tell me how you use it for this purpose?
This is specifically for IntelliJ as it’s highly recommended for Java but the
debugger is not as I
49.
Capricious loop-variable <p>Question is only for Delphi- and Pascal-programmers.</p><p>Maybe, not only I have, when loop-variable was capricious. Example:</p><blockquote>for i := 1 to n do</blockquote><blockquote><p> writeln('Spam-spam-spam');</p></blockquote><p align="left">"i" is going from n + 1 downto 2. Or in other order, unknown for me and debugger.</p><p align="left">How can it cure?</p>
and debugger.
50.
using debbuger for competitve coding Do you guys use a debugger provided by an ide or debug using print statements only
Do you guys use a debugger provided by an ide or debug using print statements
only
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