- Operation on formal power series (exp, log, sqrt, ...) (I know the general
idea ofNewton method, know the general idea of Newton method) - How to actually use generating
functions to solve problems
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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:
305— search for 305, most probably it will find blogs about the Round 305andrew stankevich contests— search for words "andrew", "stankevich" and "contests" at the same timeuser:mikemirzayanov title:testlib— search containing "testlib" in title by MikeMirzayanov"vk cup"— use quotes to find phrase as istitle:educational— search in title
Results
1.
Newton
Last visit:
8 months ago
Registered:
7 years ago
2.
Things I don't know I'm just in a mood to shitpost. Don't take it too seriously.
Things that I have heard of, but don't know (imagine how many things I haven't even heard of):
- Li-Chao Segment Tree
- Segment Tree Beats
- RMQ in $O(n)$/$O(1)$
- Any self-balancing tree except treap
- Link-cut tree
- Wavelet tree
- Mergesort tree
- Binomial heap
- Fibonacci heap
- Leftist heap
- Dominator tree
- 3-connected components in $O(n)$
- $k$-th shortest path
- Matching in general graph
- Weighted matching in general graph
- Preflow-push
- MCMF in $O(poly(V, E))$
- Minimum arborescence (directed MST) in $O(E \log V)$
- Suffix tree
- Online convex hull in 2D
- Convex hull in 3D
- Halfplane intersection
- Voronoi diagram / Delaunay triangulation
- Operation on formal power series (exp, log, sqrt, ...) (I know the general idea of Newton method)
- How to actually use generating functions to solve problems
- Lagrange Inversion formula
- [...
3.
CDQ convolution (online FFT) generalization with Newton method Hi everyone!
This is yet another blog that I had drafted for quite some time, but was reluctant to publish. I decided to dig it up and complete to a more or less comprehensive state for the [$300 contest](https://codeforces.me/blog/entry/110840).
Essentially, the blog tells how to combine CDQ technique for relaxed polynomial multiplication ("online FFT") with linearization technique from Newton method (similar approach is used in the first example of the [ODE blog post](https://codeforces.me/blog/entry/76447) by [user:amiya,2023-01-14]), so that the functions that typically require Newton's method can be computed online as well. I will try to briefly cover the general idea of "online FFT" too and provide some examples, in case you're not well familiar with it. That being said...
[cut]
<hr>
Consider the following setting:
There is a differentiable function $F(x)$ such that $F(0)=0$ and a polynomial $f(x)$.
You want to compute first $n$ coefficients of a formal power...
CDQ convolution (online FFT) generalization with Newton method, ("online FFT") with linearization technique from Newton method (similar
approach is used in the first, Newton method (similar approach is used in the first example of the [ODE blog
post](https
4.
OCPC 2025 Summer season — wrap Hi everyone!
<center><a href="https://ocpc.camp"><img src="https://ocpc.camp/images/ocpc_light.svg" height="100px"></a>
<a href="https://icpc.foundation/"><img src="/predownloaded/43/08/43086529a28ccb5c9f2f2eec560ffa85e09c6881.svg" height="100px"></a></center>
Just recently, the last mirror of the summer season of OCPC 2025 has concluded. I would like to take this moment to share some of the details and statistics on how it went with the community 😊
[cut]<br>
### ICPC award
Okay, this happened last chronologically, but it's probably most relevant, so I will start with it!
<center>
<a href="/predownloaded/43/df/43dfc0edaaa29db59b2b5ba6afbd4f033c8b535f.jpg"><img src="/predownloaded/43/df/43dfc0edaaa29db59b2b5ba6afbd4f033c8b535f.jpg" height="200px"></a>
<a href="/predownloaded/b9/25/b9256e789a31ab2d1b3858bfa984ea1341dbc6c5.jpg"><img src="/predownloaded/b9/25/b9256e789a31ab2d1b3858bfa984ea1341dbc6c5.jpg" height="200px"></a>
<a href="/predownloaded/c5/21/...
organization, GoForGold (by Newton School of Technology), was making training
camps in India. In particular
5.
Codeforces Round #519 Editorial #### [1043A — Elections](http://codeforces.me/contest/1043/problem/A)
<spoiler summary="Tutorial">
We can observe that result cannot exceed $201$ — Awruk gets at least $101$ votes from one person and Elodreip cannot get more than $100$ votes from one person. So we can iterate over every possible integer from $1$ to $201$ and check if Awruk wins with $k$ set to this integer. We have to remember that $k$ — $a_i$ is always at least $0$, so we have to check this condition too. Complexity $O(n * M)$, where $M$ denotes maximum possible value of $a_i$. Try to solve it in $O(n)$.
</spoiler>
<spoiler summary="Solution">
~~~~~
#include <bits/stdc++.h>
using namespace std;
int n;
int mx = 0, sum = 0;
int main(){
scanf("%d", &n);
for(int i = 1; i <= n; ++i){
int a; scanf("%d", &a);
mx = max(mx, a);
sum += a;
}
sum *= 2;
sum += n;
sum /= n;
printf("%d", max(sum, mx));
return 0;
}
~~~~~
</spoiler>
Author: [user:FCB1234,201...
for(int i = 1; i < 20; ++i){ for(int j = N - 1; j >= 1; --j){ dp[i][j] = newton
(cnt[j], i, int newton(int a, int b){ if(b < 0 || a < b) return 0; return (((1LL * sil[a] *
odw[b])%MX
Tutorial of Codeforces Round 519 by Botan Investments
6.
GoForGold Camp 2024 — Wrap I just returned from the **1st** edition of the [**GoForGold** camp](https://codeforces.me/blog/entry/135929) in India 🇮🇳, where I had the privilege of teaching some of the brightest Indian students as they prepare for the upcoming ICPC World Finals.
After organizing camps in [Syria](https://codeforces.me/blog/entry/118493), [Uzbekistan](https://www.linkedin.com/feed/update/urn:li:activity:7144180416655118336/), Azerbaijan, and [Croatia](https://codeforces.me/blog/entry/134097), this was yet another incredible experience of helping students push closer to their competitive programming goals.
A highlight of this trip was witnessing the unique approach of Newton School of Technology. They brought teachers right from industry to university to fill the gap — a truly innovative structure that left a lasting impression.
Congratulations to the top three winners in Div. 1:<br>
🥇 [404_solution_not_found](https://codeforces.me/team/168505): [user:P.V.S...
[user:Enigma27,2024-12-15] Gour for inviting me and the Newton School of
Technology for their warm, competitive programming goals. A highlight of this trip was witnessing the
unique approach ofNewton, A highlight of this trip was witnessing the unique approach of Newton School of
Technology. They
7.
Newton School Grand Coding Contest 2022 Editorial #### A. First Day at Newton School
------------------
<spoiler summary = "Solution">
~~~~~
//C++ implementation
#include <iostream>
#include <string>
using namespace std;
int main ()
{
string s;
cin >> s;
if (s == "Apple") cout << "Gravity";
else cout << "Space";
}
~~~~~
</spoiler>
#### B. A Growing Rivalry
------------------
<spoiler summary = "Solution">
Let the number of rounds won by Nutan be $n$ and that won by Tusla be $t$. As $n + t = L$, we are given that $n + t$ is odd. Thus, we have $n \neq t$ as otherwise $n + t$ will be even. So we can see that there is no draw possible, one of Nutan or Tusla must have won more rounds than the other. To find whom, we first initialize $n = t = 0$. We will then iterate through each character of the string $S$. If the character is 'N', we increment $n$ by $1$, otherwise we increment $t$ by $1$. After we have finished iterating the string, if $n < t$ then Tusla has won, otherwise Tesla has won. You ca...
Newton School Grand Coding Contest 2022 Editorial, #### A. First Day at Newton School ------------------, #### G. Newton And Keppler ------------------
8.
Lagrange interpolation and partial fraction decomposition Hi everyone!
Today I'd like to write yet another blog about polynomials. Specifically, I will cover the relationship between polynomial interpolation and Chinese remainder theorem, and I will also highlight how it is useful when one needs an explicit meaningful solution for partial fraction decomposition.
[cut]<br>
#### Lagrange interpolation
It's quite well-known that the system
$$\begin{cases}P(x_0) = y_0, \\ P(x_1) = y_1, \\ \dots \\ P(x_n) = y_n\end{cases}$$
has a unique solution $P(x)$ among polynomials of degree at most $n$. A direct way to prove that $P(x)$ exists is through Lagrange's interpolation. To have a better grasp of it, let's recall that $P(x) \equiv P(x_0) \pmod{x-x_0}$, thus system becomes
$$\begin{cases}P(x) \equiv y_0 \pmod{x-x_0}, \\ P(x) \equiv y_1 \pmod{x-x_1}, \\ \dots \\ P(x) \equiv y_n \pmod{x-x_n}.\end{cases}$$
From the Chinese remainder theorem follows that $P(x)$ is unique modulo $Q(x) = (x-x_0)\dots(x-x_n)$ and is explicitly given ...
polynomial with Newton method (Sieveking-Kung algorithm).
9.
Newton School Grand Coding Contest 2021 <b>Edit</b>: The gift vouchers have been sent to all the participants. The top 5 participants will receive an additional mail with their prizes soon.
<b>Edit</b>: The prize winners have been announced on the [Newton School Contest Page](https://my.newtonschool.co/contest/all/). Please click on the star icon next to contest details for the information corresponding to the winners. The gift vouchers will be sent to the prize winners by Friday next week (17.09.2021).
<b>Edit</b>: The editorials have been published [here](https://codeforces.me/blog/entry/94322).
Hello Geeks!!!
Assemble to compete with India’s coding community like never before! [Newton School’s Grand Coding Contest](https://my.newtonschool.co/contest/all) will be based on the Avengers theme, so it will not only be fun but plotful too!
<b>Contest link</b> — [https://bit.ly/3Dau2ZI](https://bit.ly/3Dau2ZI)
<br><b>Date</b> — 27 August 2021 (Friday)
<br><b>Time</b> — 9 PM
<br><b>Duration<...
Newton School Grand Coding Contest 2021, announced on the [Newton School Contest
Page](https://my.newtonschool.co/contest/all/). Please click on, Assemble to compete with India’s coding community like never before! [Newton
School’s Grand Coding, Edit: The prize winners have been announced on the [Newton School Contest
Page](https
10.
Optimal Algorithm on Polynomial Composite Set Power Series This is a part of my [report](https://github.com/EntropyIncreaser/ioi2021-homework/blob/master/thesis/main.tex) on China Team Selection 2021. I might translate some other parts later if you are interested.
I'm going to show that we can calculate $f(G)$ for any polynomial $f\in R[x]$ and set power series $G: 2^{n} \rightarrow R$ under $\Theta(n^2 2^n)$ operations on $R$.
Let's first consider a special case: calculate $F = \exp G$. We consider set power series as truncated multivariate polynomial $R[x_1,\dots,x_n]/(x_1^2,\dots,x_n^2)$. We can see that $F' = FG'$ whichever partial difference $\frac{\partial}{\partial x_k}$ we take. Then we can rewrite this equation as $[x_n^1] F = ([x_n^1]G)\cdot [x_n^0]F$. Hence we reduced the problem into calculating $[x_n^0] F$, and then one subset convolution gives the rest part. The time complexity is $T(n)=\Theta(n^22^n) + T(n-1)$, which is exactly $\Theta(n^22^n)$. I call this method "Point-wise Newton Iteration".
This method sounds more r...
) + T(n-1)$, which is exactly $\Theta(n^22^n)$. I call this method "Point-wise
Newton Iteration".
11.
Newton's Grand Contest 2022 Invite <b>Edit</b>: The problems have been opened for practice, the [editorials](https://codeforces.me/blog/entry/101122) have been published!
Warm greetings,
[Newton School](https://www.newtonschool.co/grandcodingcontest) cordially invites you to be a part of our [Newton's Grand Coding Contest](http://bit.ly/NSGrandContest_CF). The challenge will go live on **31st March 2022 at 9 PM IST**. Do register for the contest and stand a chance to win cash prizes worth **₹1,000,000** and exciting goodies like **AirPods 3rd Gen, Amazon Echo 4th Gen, boAt Airdopes 131, ergonomic keyboards, [Newton School](http://bit.ly/NSGrandContest_CF) exclusive merchandise** (T-shirts, sippers, notebooks, stickers, etc.)
<p>
Registration Link: [Newton's Grand Coding Contest](http://bit.ly/NSGrandContest_CF) — we have already caused 100,000 registrations.
<p>
You will be given **8 problems** and **180 minutes** to solve them. The contest will be <b>rated</b> for all! The initial problems are high...
Top 100 Indian Participants: Exclusive Newton School T-shirts and goodies!
, [Newton School](https://www.newtonschool.co/grandcodingcontest) cordially
invites you to be a part
12.
Invitation to CodeChef Starters 183(Rated till 6-Stars) — 23th April We invite you to participate in CodeChef’s [Starters 183](https://www.codechef.com/START183), this Wednesday, 23th April, rated for 6 stars.
Time: [8:00 PM — 10:00 PM IST](https://www.timeanddate.com/worldclock/fixedtime.html?msg=CodeChef+Starters+183&iso=20250423T20&p1=44&ah=2)
Joining us on the problem setting panel are:
- Author : Shreyan [user:Dominater069,2025-04-21] Ray.
- Tester: Archit [user:pols_agyi_pols,2025-04-21] Kumar.
Written editorials will be available for all on discuss.codechef.com. Pro users can find the editorials directly on the problem pages after the contest. The video editorials of the problems will be available only to Pro users.
Also, if you have some original and engaging problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them [here](https://www.codechef.com/problemsetting/new-ideas).
Hope to see you participating.
Good Luck!
----
**IOI Bootcamp: Newton School of Technology (NST)**
Ar...
**IOI Bootcamp: Newton School of Technology (NST)**
13.
Insomnia'26 Editorial ####[Problem A : Ancient Trees](https://codeforces.me/gym/680528/problem/A)
Problem Idea: [user:shorya1835,2026-03-23],
Problem Preparation: [user:aastik231205,2026-03-23]
<spoiler summary="Hint 1">
You are allowed to use intermediate vertices in your sequence. Does it ever actually help? For any three vertices $a$, $b$, $c$, what is the relationship between $c(a,b) + c(b,c)$ and $c(a,c)$? Recall that for non-negative integers, $x + y \geq x \oplus y$.
</spoiler>
<spoiler summary="Answer for Hint 1">
Since, $c(a,b) + c(b,c) \geq c(a,b) \oplus c(b,c)$, Splitting the path doesn't minimize the distance at all.
Hence $d(u,v) = c(u,v)$ always.
</spoiler>
<spoiler summary="Hint 2">
Since $d(u,v) = c(u,v)$ always, we can maintain a running mask $M$ (XOR of all Type 1 updates so far). A path with $\ell$ edges has its XOR-distance changed only if $\ell$ is odd, flipping their XOR-distance by $M$, depending only on the running XOR of Type 1 queries so far. Can you precomput...
// Compute inverse of b_rev using Newton iteration // We need precision of
deg_q + 1 int
Tutorial of Insomnia-26
14.
CodeRush-X Invite (Win prizes worth $12,500) <p>
<b>Update</b>: The contest has been shifted to **12th April 2023, 9 PM IST** to stabilise the revamps to the platform architecture. Apologies for the inconveniences caused.
<p>
<b>Update</b>: The contest has been shifted to **4th February 2023, 9 PM IST** (different problem set). We sincerely apologize for the inconvenience caused by the recent contest crash. We understand that many of our valued participants were affected by this issue and we deeply regret any frustration or disappointment this may have caused. Rest assured that we are taking all necessary steps to prevent such an incident from happening in the future and to ensure that all participants have a fair and enjoyable experience. Thank you for your understanding and patience.
Warm greetings,
Newton School cordially invites you to be a part of our [CodeRush-X](https://my.newtonschool.co/course/jovbcci1trlf/assignment/jzvskoymtdtu/dashboard/?tab=questions). The challenge will go live on **28th January 2023 at ...
Top 100 Indian Participants: Exclusive Newton School T-shirts and goodies!
, Newton School cordially invites you to be a part of our
[CodeRush-X](https://my.newtonschool.co
15.
To Infinity and Beyond When someone says nobody ain't doing no thing with CF, I be like
So, haven't you met the average Joe that keep saying that "efficiency is not that important", "my [Greedy wrong sh*t] solution is certainly correct", "who's Dijkstra"? You will. Therefore, we'll be...
### Cutting to the chase
And show some situations where competitive programming was particularly useful. I would really like to hear more solutions as I am myself a CF Avg. Joe. [cut]
#### Local extremes
**The problem:**
Find all local extreme points on a given 2D surface with given heights. You can imagine something like the previous picture, but in the specific context all values were taken from some function(consider it O(1)), so you wouldn't actually need to iterate through all the data.
**Avg. Joe:**
- DFS — ples avg. Joe
**CF Joe:**
- [Newthon's method...
- [Newthon's method](https://en.wikipedia.org/wiki/Newton%27s_method) - [hill
climbing](https
16.
GoForGold IOI Bootcamp — India <center>
<img height="100px" src="/predownloaded/67/2f/672f239a4b390e85db2408790f5907770547fdb2.jpeg">
<img height="90px" src="/predownloaded/6b/b4/6bb4c1baf053e08ac2257bee4fe8c479b133272b.png">
</center>
Hi everyone!
We are thrilled to announce that the [GoForGold](https://goforgold.in/) IOI Bootcamp is coming this Summer, on **May 25-June 6, 2025**! After carefully considering various academic schedules, competition dates, and feedback from our community, we've selected these dates to accommodate as many talented young programmers as possible.
This intensive training program will be hosted at the [Newton School of Technology](https://www.newtonschool.co/newton-school-of-technology-nst/home) Campus in Sonipat, Delhi, and is brought to you by the GoForGold.
The bootcamp is specifically designed to prepare talented students for the International Olympiad in Informatics by providing intensive training, practice, and mentorship. Our goal is to expand India's competitive pr...
GoForGold is an initiative by Newton School of Technology (NST) to foster a
culture of competitive, This intensive training program will be hosted at the [Newton School of
Technology](https
17.
Convex Optimization for CP, Part 1: What is Convex Optimization? **Before we begin: This blog is my attempt to [Codeforces Month of Blog Posts](https://codeforces.me/blog/entry/110840). Simple rule: Write an interesting CodeForces blog post until February 15th and win $300.**
In this blog, I will be describing the concept of Convex Optimization, and techniques that can be used to solve Convex Optimization tasks. The blog will be divided into two parts — "What is Convex Optimization", and "How do we solve Convex Optimization tasks". This part of the blog is for "What is Convex Optimization". [(Part 2 is here)](https://codeforces.me/blog/entry/111048)
--------
### **What is Convex Optimization?**
"A convex optimization problem is an optimization problem in which the **objective function is a convex function** and the **feasible set is a convex set**." as Wikipedia says. This may be hard to understand for many people, so let's use the simpler case of a univariate function. Often the "convex function" is called "unimodal function" in...
://en.wikipedia.org/wiki/Newton%27s_method_in_optimization). Not many convex
optimization tasks have
18.
2018-2019 ACM-ICPC, Asia Jiaozuo Regional Contest, Editorial SPOILER ALERT: Please do not read these hints if you want to solve some problems in this contest but haven't attempted yet.
<spoiler summary="DO NOT open if you want to solve them by yourself">
Hints are categorized by the number of accepted teams.
<spoiler summary="hints for ADEFI">
[problem:102028A]
<spoiler summary="hint for A">
Read and implement.
</spoiler>
[problem:102028D]
<spoiler summary="hint for D">
There are only two cases, so just draw them on draft paper.
</spoiler>
[problem:102028E]
<spoiler summary="hint for E">
The resistance of the $n$-th section is a multiplicative function of $n$, which only depends on distinct prime factors.
</spoiler>
[problem:102028F]
<spoiler summary="hint for F">
BFS is enough.
Be careful with leading whitespaces and too many test cases.
</spoiler>
[problem:102028I]
<spoiler summary="hint for I">
Picking half of points from every boundary is enough.
</spoiler>
</spoiler>
<spoiler summary="hints for ...
(or Newton iteration).
19.
Invitation to Turing Cup 2K26 — organized by Turing Hut, VNRVJIET (Prizes worth Rs 75,000) 
Greetings, Codeforces community!
We, [**Turing Hut**](https://turinghut.org), the official competitive programming club of VNRVJIET, Hyderabad, are thrilled to present our flagship event, [**Turing Cup 2K26**](https://turinghut.org/turingcup/) — _One Team, One Dream_, featuring an exciting **prize pool of ₹75,000!** This national-level coding contest is open to all undergraduate students.
### Format
**Team Size**: 1-2
This competition will be held in 2 Rounds.
**Round 1**: <s>Thursday, February 26th, 2026 at 20:30 IST</s> [**Saturday, February 28th, 2026 at 20:30 IST**](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Turing+Cup+2K26+Round-1&iso=20260228T2030&p1=505&ah=1&am=30). This round will last for **90 minutes** and will be held online. The contest link will be mailed to the participants 3 hours before the commencement of the round. Shortlisted teams for round 2 will be notifi...
10. Team A (Newton School Of Technology) (4 / 6) —
[user:hk_patel_9118,2026-03-03]
20.
Proof for an interesting 2-person 0-sum game One of my friends [user:VS-Codes,2023-10-01] recently introduced me to an Alice-Bob game problem (Newton School CodeRush September '23 — Problem C) which goes as follows —
<spoiler summary="The Problem">
Alice and Bob are playing a game. They start with $n$ piles of $1$ stone each. Alice always makes the first move. At any turn, a player can choose any **two** non-empty piles and merge them into one large pile, _provided that the total number of stones in the new composite pile does not exceed $m$_. If at any point, a player is unable to make a move, he/she loses the game and the opponent is declared the winner. Find out who wins the game if both Alice and Bob play optimally.
For example, let $n = 6$ and $m = 2$. The game may proceed as follows:
- Initially there are $6$ piles of $1$ stone each $[1, 1, 1, 1, 1, 1]$.
- Alice merges the $3^{rd}$ and $4^{th}$ piles to get $[1, 1, 2, 0, 1, 1]$.
- Bob merges the $1^{st}$ and $5^{th}$ piles to get $[2, 1, 2, 0, 0, ...
(Newton School CodeRush September '23 — Problem C) which goes as follows —
21.
Call for Problem Ideas for GoForGold Long Challenges Hello, Codeforces Community!
We are excited to announce the **[GoForGold](https://goforgold.in/)** Long Challenges—an innovative monthly contest series brought to you by **[Newton School of Technology](https://www.newtonschool.co/newton-school-of-technology-nst/home)**. Starting on the second last Friday of every month, these challenges will run for 10 days, providing a fantastic platform to learn new things and hone your problem-solving skills.
As the Contest Coordinator, I invite you to share your creative problem ideas with us. This is a unique opportunity where you don't have to prepare a full-fledged problem—simply submit your idea. If your idea is accepted, you'll be rewarded with a cash prize!
Below is the reward structure based on the difficulty and corresponding Codeforces rating:
<table width="100%">
<thead>
<tr>
<th>Difficulty</th>
<th>CF Difficulty Rating</th>
<th>Idea Reward (USD)</th>
</tr>
</thead>
<tbody>
<tr>
...
monthly contest series brought to you by **[Newton School of Technology](https
22.
Codeforces Round #163 (Div. 2) Tutorial [problem:266A]
In this problem you should count number of consecutive pairs of equal letters. It can be done using one cycle and $O(N)$ time.
[problem:266B]
In this you should realize the given process. You should $t$ times swap elements $i$ and $i+1$ if on the place $i$ was a girl and on the place $i+1$ was a boy. You should not push some girl to the left multiple times at once. The solution can be written using $O(N \cdot T)$ time.
[problem:266C]
This problem can be solved using constructive algorithm. We will use inductive approach. At first, we have matrix of size $n$ and $n-1$ ones in it. Therefore, there is a column with no ones in it. So, we put this column to $n$-th place. In this case, the lower right element will be $0$. Then find any row with at least one integer one and put it to the $n$-th place.
After these operations the element in cell $(n, n)$ equals to $0$ and the last row has at least one integer one. Therefore, we can reduce the dimension of our p...
tree and the Newton binomial, with all powers that are less than $j$ (these
values can also
Tutorial of Codeforces Round 163 (Div. 2)
23.
Newton's Coding Challenge January 2022 Invite Warm greetings,
[Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **28th January 2022 at 9 PM IST**. Also, do register for [Newton's Grand Coding Contest 2022](https://www.newtonschool.co/grandcodingcontest) and stand a chance to win prizes upto ₹1,000,000.
<p>
Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/)
<p>
You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all!
<p>The problems were written and tested by [user:_Enigma__,2022-01-28], [user:ShlokG,2022-01-28], and [user:iLLusio,2022-01-28].
<p>
We would also like to thank [user:gkapatia,2022-01-28] for co-ordinating the contest.
<p>
Highlights of contest:
<ol>
<li>The Prize Money for the top 5 performers are as follows:
<ul>
<li> First Prize: **₹10,000**
<li> Second Prize: **₹5,000...
[Newton School](https://www.newtonschool.co/) cordially invites you to be a
part of our [monthly
24.
Newton Editorial 2022 October [A. Completing the square](https://my.newtonschool.co/playground/code/b5o0maa29vy5/)
------------------
<spoiler summary = "Solution">
~~~~~
#include <bits/stdc++.h>
using namespace std;
int main(){
int n;
cin>>n;
cout<<n*n<<endl;
}
~~~~~
</spoiler>
[B. Fireworks](https://my.newtonschool.co/playground/code/t5x2lwkk9r09/)
------------------
<spoiler summary = "Hint">
What is the maximum possible value of $d(M)$.
</spoiler>
<spoiler summary = "Solution">
We can see that for $ M \le 10^18$, the maximum possible value of $d(M)$ is only $ 9 * 18$ attained for $999999999999999999$. So for finding the number of solutions for a given $N$, we can iterate over all the values of $d(M)$ upto $9 *18$, and then check if $d(N/p) == p$.
</spoiler>
[C. Lights](https://my.newtonschool.co/playground/code/8vn89k2p7y5e/)
------------------
<spoiler summary = "Hint">
Try solving the easier version of the problem where we only need to find the number of distin...
Newton Editorial 2022 October
25.
Newton's Coding Challenge May 2021 Invite <b>Update: Due a clash with CF round, the contest start time has been moved to 10pm<b>
Warm greetings,
[Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **28th May 2021 at 10 PM IST**. The contest will be based on the storyline of the **Game of Thrones**, so don't miss the fun!
<p>
Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/)
<p>
You will be given **6 problems** and **150 minutes** to solve them.
<p>The problems are written and prepared by [user:aniket9465,2021-05-28] and [user:swapnil07,2021-05-28].
<p>
We would also like to thank:
<li> [user:gkapatia,2021-05-28] for co-ordinating the contest.
<li> [user:jiraya_,2021-05-28] and [user:ak532,2021-05-28] for the valuable feedback throughout.
<p>
Highlights of contest:
<ol>
<li>The Prize Money for the top 5 performers are as follows:
...
[Newton School](https://www.newtonschool.co/) cordially invites you to be a
part of our [monthly
26.
Invitation to NextTuring 2026 (₹23k prize pool; Individual CP Contest) Onsite group link: [https://codeforces.me/group/EP1lUFnsjA](https://codeforces.me/group/EP1lUFnsjA)
UPD: Final Results announced! [standings:688815]
Greetings, CP community!
==================
We are glad to invite all college students in India to take part in the preliminary round of NextTuring 2026 on 19 April 9:05 PM IST (GMT +5:30)
NextTuring 2026 is an individual CP Contest. The preliminary round is of 2 hours and consists of 5 to 8 problems. (Approx. Div 4 to Div 3 level problems will be given)
The top performers of the preliminary round will be invited to take part in an onsite round @ NST Bengaluru on 26 April 2026. The onsite round will be a part of our college's Tech Fest — AAYAM 2026
Prizes
------------------
~mediocre,2026-04-26 — 1st place: ₹10,000
~espacio,2026-04-26 — 2nd place: ₹6,000
~Krritin,2026-04-26 — 3rd place: ₹4,000
~optimus_maximus,2026-04-26 — 4th place: ₹2,000
[user:nishtha.agarwal.211,2026-04-2...
[Registration Link](https://unstop.com/hackathons/nextturing-aayam-newton
-school-of-technology
27.
Mathematics behind Machine Learning: Beating Least Squares in Only 1 Iteration **Motivation**
==================
Updating weights in each layer is the core of tuning a Neural Network. Now consider a simple regression model. If I ask you what method we use to update the weights? You'll probably reply — the method of least squares. And that is the most common thing. But it is to be noted that, Least Squares may not always be the most optimal method of updating weights. In this blog, I'd want to tell you about a very powerful method to get the weights. And if you have studied Numerical Analysis, you probably know about this. It's nothing but the very popular **Newton-Raphson Method**.
Well in general, this is used to solve equations numerically which are not solvable analytically. If we simply have to define the method, it will be something as follows:
Consider the equation, $f(x)=0$.
Then, we can solve for $x$ starting from any initial guess $x^{(0)}$; and for the $i$-th iteration, the update of the solution $x$ is given by,
$x^{(i)} = x^{(i-1)} ...
In the $k$-th iteration of the Newton-Raphson method, for multidimensional
quantities, we have,, Let's begin iterations of Newton-Raphson method with $\Theta^{(0)}=O$. Then we
end up with, That's the final result that we obtain in this method. Now let's talk about the
Newton-Raphson, While solving general scalar equations, we usually do 3-4 iterations of the
Newton-Raphson method
28.
CodeHive Editorial (College Organized Contest) The _CodeHive Coding Competition_ was organized by the Newton School Coding Club at PCCOE on the HackerRank platform. The contest was designed to start with very basic concepts and gradually increase in difficulty.
The whole contest can be accessed via the following link: [CodeHive Contest](https://www.hackerrank.com/contests/codehive)
For all participants, the links to the questions and their respective editorials are provided below:
1. Explore Pandora: [Problem Link](https://www.hackerrank.com/contests/codehive/challenges/explore-pandora)
- Editorial: https://codeforces.me/blog/entry/112129
2. Survival Match: [Problem Link](https://www.hackerrank.com/contests/codehive/challenges/survival-game-2-1)
- Editorial: https://codeforces.me/blog/entry/112069
3. Bitwise Education: [Problem Link](https://www.hackerrank.com/contests/codehive/challenges/learning-technology)
- Editorial: https://codeforces.me/blog/entry/112087
4. Dragon Race: [Problem Link](https://...
Best regards,
Newton School Coding Club,
Pimpri Chinchwad College of Engineering
29.
CodeRush January 2024 Invite **Update**: The contest goes live today at 9pm.
<p>
Warm greetings and Happy New Year everyone!
[Newton School](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-25-01-2024-blog-post&utm_namespace=coderush&utm_hash=ns_c1cicxcclecv) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-25-01-2024-blog-post&utm_namespace=coderush&utm_hash=ns_c1cicxcclecv). The challenge will go live on **29th January 2024 at 9 PM IST**.
<p>
Registration Link: [CodeRush](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-25-01-2024-blog-post&utm_namespace=coderush&utm_hash=ns_c1cicxcclecv)
<p>
You will be given **6 problems** and **150 minutes** to solve them. The ...
[Newton
School](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source
30.
[Editorial] Newton School December 2021 Contest Credits: [user:Lubba_Lubba,2021-10-30], [user:dnshgyl21,2021-10-30], [user:Sawarnik,2021-10-30], [user:Xzirium,2021-10-30]
#### [A. AC or not?](https://my.newtonschool.co/playground/code/stlxznqa697h/)
------------------
<spoiler summary = "Solution">
Take the input in variable $n$. So if $n == 1$, print $AC$, else print $WA$.
</spoiler>
#### [B. ABBA](https://my.newtonschool.co/playground/code/kr38ahzcg1br/)
---------------------
We solve this problem in cases:
Firstly, we take the case where all the characters of the string are either ‘a’ or ‘b’. For this do not require to perform any operations as every character of the string is equal.
Secondly, we take the case where ‘a’ and ‘b’ both exist at least once. Here we can either make all the characters ‘a’ or ‘b’. We try to calculate the minimum operations required to make all characters ‘a’. We also observe that there exists a character ‘b’ with adjacent character ‘a’ since ‘a’ and ‘b’ both exist at least once. We...
[Editorial] Newton School December 2021 Contest
31.
[Editorial] Newton School August 2022 Contest #### [A. The Dragon Eggs](https://my.newtonschool.co/playground/code/w429jvr8k2wj/)
------------------
<spoiler summary = "Solution">
```C++
#include<bits/stdc++.h>
using namespace std;
```
signed main() {
int g, s, a, b;
cin >> g >> s >> a >> b;
cout << ((g * a >= s * b) ? "Gold" : "Silver");
return 0;
}
</spoiler>
#### [B. The Clash of the Houses ](https://my.newtonschool.co/playground/code/qr4j78jsds5a/)
------------------
<spoiler summary = "Solution">
Since $i^{th}$ and ${i+k/2}^{th}$ character must be same, and also first half of string is equal to last half of string, this implies that the answer is "1" if and only if count of $1s$ is divisible by 4.
</spoiler>
<spoiler summary = "Code">
```C++
#include<bits/stdc++.h>
using namespace std;
signed main() {
int t;
cin >> t;
for(int i=0; i<t; i++) {
int n;
cin >> n;
string s;
cin >> s;
int cnt = 0;
for(int j=0; j<n; j++) {
if(s[j] == '1') cnt++;
}
if(cnt % 4 ...
[Editorial] Newton School August 2022 Contest
32.
Newton School Grand Coding Contest 2021 Editorial #### [A. Thor vs Loki](https://my.newtonschool.co/playground/code/waeqyqd0i8mw/)
------------------
<spoiler summary = "Solution">
The strength of Thor is $z - x$, and that of Loki is $z - y$. Thus, the maximum strength is $\text{max}(z-x, z-y)$. Equivalently, we can also say the maximum strength is $z - \text{min}(x, y)$.
Complexity: $O(1)$
</spoiler>
#### [B. Archery](https://my.newtonschool.co/playground/code/lyk5chtoejlx/)
------------------
<spoiler summary = "Hint 1">
Think of what strategy to take based on the number of monsters of each type.
</spoiler>
<spoiler summary = "Hint 2">
Think of what to do with types that have a large number of monsters. Then, think of what to do with the other ones.
</spoiler>
<spoiler summary = "Solution">
The optimal strategy is:
1. First, shoot down all monsters of a particular type if there are more than $k$ of them. Do this until there are no more types with more than $k$ monsters.
2. The remaining monsters can ...
Newton School Grand Coding Contest 2021 Editorial
33.
[Editorial] Newton School September 2021 Contest Credits: [user:Lubba_Lubba,2021-10-30], [user:dnshgyl21,2021-10-30], [user:Sawarnik,2021-10-30], [user:Xzirium,2021-10-30]
#### [The Easy One](https://my.newtonschool.co/playground/code/kjch6n8dsh9r/)
------------------
Simply sort the three numbers, then print the second number, or otherwise do the same with a few if-else statements.
#### [Love For Subsets](https://my.newtonschool.co/playground/code/ku3232d5n1zc/)
------------------
It can be shown that the optimal way is to first take all the odd numbers, then out of the remaining take those which are congruent to 2 mod 4. Then those which are congruent to 4 mod 8, then 8 mod 16 and so on. Using simple maths, it can be done in logn time.
#### [Max Out Parallelogram](https://my.newtonschool.co/playground/code/y8a9l80z5ypk/)
------------------
First we recall an important property of a parallelogram, the opposite sides are parallel and equal. The area of any parallelogram is equal to the length of any side multiplied...
[Editorial] Newton School September 2021 Contest
34.
[Editorial] Newton School April 2022 Contest #### [A. Mex of 2 ](https://my.newtonschool.co/playground/code/uq6x8mrk9wei/)
------------------
<spoiler summary = "Solution">
If neither of $A$ or $B$ equals to zero, print $0$. Otherwise if neither of them equal $1$ then print $1$, else if neither of them equal $2$, print $2$.
</spoiler>
#### [B. Array & Xor ](https://my.newtonschool.co/playground/code/p4jhssnhhshw/)
------------------
<spoiler summary = "Solution">
If all the entries of the array are zero, then the answer is $0$.
Otherwise, if the xor of all the elements in the array is zero, then the answer is $1$. (We can select the entire array in the move).
Finally, in all other cases the answer is $2$. This is because we can select the entire array in the first move, and then again select the entire array in the second move.
</spoiler>
#### [C. Grids & Modulus ](https://my.newtonschool.co/playground/code/p4jhssnhhshw/)
------------------
<spoiler summary = "Solution">
The first observatio...
[Editorial] Newton School April 2022 Contest
35.
100 Problems, Countless Lessons: My Competitive Programming Journey So Far ## 100 Problems: A Small Personal Checkpoint
Hey everyone,
This is not a milestone post.
It is more like a diary note.
A few days ago, I noticed that I had crossed 100 solved problems on Codeforces.
On Codeforces, that number is not impressive at all.
Many people solve that much very quickly.
But for me, it felt worth pausing for a moment.
=====================================
### Why This Matters To Me
When I joined Codeforces four months ago, I was completely lost.
I had:
- zero competitive programming experience
- a Python IDE
- a cup of chai
- and a lot of confusion
Even opening a Div2 contest felt intimidating.
Not because the problems were impossible, but because I did not know how to think in that environment.
So this post is not about achievement.
It is about acknowledging a small personal win: consistency.
=====================================
### What Changed
In the beginning, everything felt overwhelming.
- What is Div2?
- ...
Source Contributor Contests: LeetCode, CodeChef, Codeforces, Newton Learning
one problem at a time, starters, Codeforces rounds, Newton practice contests.
36.
CodeRush March 2024 Invite <b>Update</b>: The contest goes live today, **4th March 2024 at 9 PM IST**.
Warm greetings!
[Newton School](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-27-02-2024-blog-post&utm_namespace=coderush&utm_hash=ns_u5naide7gn47) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-27-02-2024-blog-post&utm_namespace=coderush&utm_hash=ns_u5naide7gn47). The challenge will go live on **4th March 2024 at 9 PM IST**.
<p>
Registration Link: [CodeRush](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-27-02-2024-blog-post&utm_namespace=coderush&utm_hash=ns_u5naide7gn47)
<p>
You will be given **6 problems** and **150 minutes** to solve them. The contest ...
[Newton
School](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source
Codeforces (c) Copyright 2010-2026 Mike Mirzayanov
The only programming contests Web 2.0 platform
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