Combinatorics Last Updated : 07 Apr, 2025 Comments Improve Suggest changes Like Article Like Report Combinatorics is the branch of Mathematics dealing with the study of finite or countable discrete structures. It includes the enumeration or counting of objects having certain properties. Counting helps us solve several types of problems such as counting the number of available IPv4 or IPv6 addresses. Permutation and Combination are fundamental concepts in combinatorics that help us solve problems involving arrangements and selections. While permutation deals with arranging objects in a specific order, combination focuses on selecting objects without considering the order. Permutation and Combination for Students and BeginnersThis section introduces basic concepts like factorial, permutations, and combinations with easy explanations for new learners.FactorialFundamental Counting PrinciplePermutation Permutation FormulasCombination Combination FormulasDifference between Permutations and CombinationsPrinciple of Inclusion and ExclusionReal-Life Applications of Permutations and CombinationsPermutation and Combination for Aptitude PreparationPractice aptitude-style problems and quizzes to prepare for competitive exams using permutations and combinations.Permutation and Combination – Aptitude Questions and AnswersProblem on permutations and combinations - set 1 | set 2Problems On Permutations | Set 1Permutation and Combination- QuizAdvanced Topics of Permutation and Combination Explore deeper topics like permutation groups, their properties, and related theorems in advanced combinatorics.Permutation Groups and Multiplication of PermutationInverse of Permutation Group Order of Permutation GroupEven and Odd Permutations and their theoremsPermutation and Combination for Programmers This section covers coding problems based on permutations and combinations, helping you implement logic and solve real-world programming challenges.Program to calculate value of nCr using RecursionPermutations of given StringAll Permutations of an ArrayWays to sum to N using Natural Numbers up to K with repetitions allowedCount all possible N-length vowel permutationsGenerate a combination of minimum coinsNumber of ways to go from one point to another in a gridDifferent ways to represent N as sum of K non-zero integersNumber of arrays of size N whose elements are positive integers and sum is KGenerate all cyclic permutations of a number Comment More infoAdvertise with us Next Article Combinatorics C Chirag Manwani Improve Article Tags : Misc Engineering Mathematics GATE CS Pigeonhole Principle Discrete Mathematics +1 More Practice Tags : Misc Similar Reads Discrete Mathematics | Representing Relations Prerequisite - Introduction and types of Relations Relations are represented using ordered pairs, matrix and digraphs: Ordered Pairs - In this set of ordered pairs of x and y are used to represent relation. 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