Yet again on C++ input/output Hello! I wish to continue the discussion on C++ input/output performance, which was [started](http://codeforces.me/blog/entry/562) by [user:freopen,2012-09-05] long ago. [user:freopen,2012-09-05] compared the speed of the two common input/output methods in C++: the stdio library, inherited from C (`<stdio>`), and the newer iostreams library (`<iostream>`/…). However, these tests did not account for the fact that there are several important iostreams optimizations which can be used. They have been mentioned more than once on Codeforces ([first](http://codeforces.me/blog/entry/10), [second](http://codeforces.me/blog/entry/4006), [third](http://codeforces.me/blog/entry/4669)). I have written [a program](https://bitbucket.org/andreyv/cppiotest/src/tip/iotest.cpp) that compares performance of the stdio and iostreams libraries with these optimizations turned on. [cut]   **UPD1**: Added information on `_CRT_DISABLE_PERFCRIT_LOCKS`.<br/> **UPD2**: Added `printf()`/`scanf()` ca...

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A simple C++ input-stream manipulator to discard all characters until and including the new-line character Hello Codeforces, It is well-known that [C++ Input/output manipulators](https://en.cppreference.com/w/cpp/io/manip) such as `fixed`, `setprecision`, `endl`, etc. are helper functions that serve as user-friendly control commands to input/output streams. An input-stream command that is necessary but not common in competitive programming is _to discard all characters until and including the new-line character_. An example for this issue is the following [HackerEarth problem](https://www.hackerearth.com/practice/algorithms/string-algorithm/basics-of-string-manipulation/practice-problems/algorithm/conversion-11/). Although the problem is very easy, its data-input invovles a trick that the input string in each line can include a space character as a part of the string. Using the function call [std::getline(cin,s)](https://en.cppreference.com/w/cpp/string/basic_string/getline) to read the line which includes space characters right after reading the number of test cases using the in...

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"VS Code doesn't support bits/stdc++.h" Solution If you are using Visual Studio Code (VS Code) for solving C++ problems on platforms like Codeforces and you encounter issues with `#include <bits/stdc++.h>` not being supported, here's a simple solution to get it working. - **Create a `bits` folder**: Start by creating a new folder named 'bits' in the same directory where your main C++ files for problem-solving are located. - **Create a header file**: Inside the `bits` folder, create a new header file named `stdc++.h`. Make sure the extension of the file is `.h` to create a valid header file. - **Add necessary headers**: Open the `stdc++.h` file and copy-paste the following commonly used C++ standard library headers into it: ~~~~~ #include <iostream> // Input/output stream objects #include <fstream> // File stream objects #include <sstream> // String stream objects #include <iomanip> // Input/output manipulators #include <string> // String class and functions #include <vector> // Dyn...

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Hackerrank C++ Challenge — Notes 1. String Stream ------------------ Header file : sstream stringstream is a stream class to operate on strings. It implements input/output operations on memory (string) based streams. stringstream can be helpful in different type of parsing. The following operators/functions are commonly used here Operator >> Extracts formatted data. Operator << Inserts formatted data. **Method str()** : returns a string object with a copy of the current contents of the stream. **Method str(string)** : sets s as the contents of the stream, discarding any previous contents. ~~~~~ std::stringstream ss; ss.str ("Example string"); std::string s = ss.str(); std::cout << s << '\n'; ~~~~~ **Common use :** One common use of this class is to **parse comma-separated integers from a string** (e.g., "23,4,56"). ~~~~~ stringstream ss("23,4,56"); char ch; int a, b, c; ss >> a >> ch >> b >> ch >> c; // a = 23, b = 4, c = 56 ~~~~~ If the >> operator returns a value, that i...

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