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Interesting Facts About Binomial Coefficients

Last Updated: 19 October 2024

A Binomial Coefficient represented as nCk has the following value.Factorial Formula:nCk = n! / [(k !) × (n – k)!]The above formula can also be re-written as the below Mul...read more

CSES Solutions - Creating Strings II

Last Updated: 06 June 2024

Given a string, your task is to calculate the number of different strings that can be created using its characters.Examples:Input: S = "aa"Output: 1Explanation: There is o...read more

Combinatorial

Competitive Programming

DSA

CSES Problems

Ways to arrange N balls of K colors with no adjacent same colors

Last Updated: 29 April 2024

Given infinite balls of K distinct colors. Count the number of ways to arrange N balls in a line such that no two adjacent balls are of same color. Since the answer may be...read more

Binary Exponentiation

Counting numbers with given digits and digit sum

Last Updated: 20 March 2024

Given a number N, count the numbers X of length exactly N such that the number X and the sum of digits of the number X have digits A and B only in their decimal representa...read more

Combinatorial

Competitive Programming

number-theory

Picked

DSA

Binary Exponentiation

Find frequency of all characters across all substrings of given string

Last Updated: 26 March 2024

Given a string S containing all lowercase characters and its length N. Find frequency of all characters across all substrings of the given string.Examples:Input: N = 3, S ...read more

Strings

Combinatorial

DSA

Find Kth smallest number among multiples of all elements of array

Last Updated: 18 April 2024

Consider an array arr[] of size N consisting of prime numbers and an integer K. The task is to find the Kth smallest number among the multiples of all elements of the arra...read more

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Number of permutations such that pair of indices having odd sum have parity = K

Last Updated: 28 February 2024

Given an array arr[] of N distinct elements along with an integer K (0 or 1). The task is to find the number of permutations of arr[] such that all possible pairs of indic...read more

Combinatorial

Geeks Premier League

DSA

Geeks Premier League 2023

Winning Game by replacing numbers with factors (Brain Game)

Last Updated: 19 May 2024

Given 2 players A and B take turns alternatively to play a game in which they have N numbers on a paper. In one turn, a player can replace one of the numbers by any of its...read more

Geeks Premier League 2023

Counting k-Length Strings with Character C Allowing Repeated Characters

Last Updated: 08 March 2024

Given a string S of length n containing distinct characters and a character C, the task is to count k-length strings that can be formed using characters from the string S,...read more

Strings

Combinatorial

Competitive Programming

Geeks Premier League

DSA

Geeks Premier League 2023

Binary Exponentiation

Counting K-Length Strings with Fixed Character in a Unique String

Last Updated: 08 March 2024

Given a string S of length n containing distinct characters and a character C , the task is to count k-length strings that can be formed using characters from the string S...read more

Strings

Combinatorial

Competitive Programming

Geeks Premier League

DSA

Geeks Premier League 2023

Binary Exponentiation

Count all ordered pairs (A, B) such that intersection of A and B becomes K

Last Updated: 26 February 2024

Given a positive integer k and an array arr[] of size n contains distinct elements, the task is to find the number of ordered pairs (A, B) that can be made where A and B a...read more

Combinatorial

Competitive Programming

binomial coefficient

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DSA

Geeks Premier League 2023

Count all ordered pairs (A, B) such that A and B are disjoint

Last Updated: 29 February 2024

Given an array arr[] of size n contains distinct elements, the task is to find the number of ordered pairs (A, B) that can be made where A and B are subsets of the given a...read more

combinatorics

Combinatorial

Competitive Programming

Geeks Premier League

DSA

Geeks Premier League 2023

Number of ways to color the balls (Ball Coloring)

Last Updated: 15 February 2024

Given N balls. All of them are initially uncolored. You have to color the balls with two colors RED and BLUE such that there can be at most 2 positions where a RED ball is...read more

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Find the number of ways to draw the last colored ball

Last Updated: 29 January 2024

Given an array balls[] representing the count of colored balls labeled from 1 to k, the task is to determine the number of ways to draw the last ball of color i before dra...read more

combinatorics

Combinatorial

Competitive Programming

Algorithms-Dynamic Programming

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Stars and Bars Algorithms for Competitive Programming

Last Updated: 29 February 2024

The Stars and Bars (also known as Balls and Urns) technique is a popular method used in Combinatorics, the study of counting and arrangement. It's a graphical way to solve...read more

combinatorics

Combinatorial

Competitive Programming

Geeks Premier League 2023

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