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HomeLeetCode ProblemsCombinatorics

Combinatorics Problems

49 Combinatorics LeetCode problems · Solve with AI-powered hints & step-by-step explanations.

62Unique PathsMedium458Poor PigsHard920Number of Music PlaylistsHard1201Ugly Number IIIMedium1359Count All Valid Pickup and Delivery OptionsHard1467Probability of a Two Boxes Having The Same Number of Distinct BallsHard1569Number of Ways to Reorder Array to Get Same BSTHard1621Number of Sets of K Non-Overlapping Line SegmentsMedium1641Count Sorted Vowel StringsMedium1643Kth Smallest InstructionsHard1735Count Ways to Make Array With ProductHard1830Minimum Number of Operations to Make String SortedHard1863Sum of All Subset XOR TotalsEasy1866Number of Ways to Rearrange Sticks With K Sticks VisibleHard1916Count Ways to Build Rooms in an Ant ColonyHard2063Vowels of All SubstringsMedium2221Find Triangular Sum of an ArrayMedium2338Count the Number of Ideal ArraysHard2400Number of Ways to Reach a Position After Exactly k StepsMedium2514Count AnagramsHard2597The Number of Beautiful SubsetsMedium2842Count K-Subsequences of a String With Maximum BeautyHard2928Distribute Candies Among Children IEasy2929Distribute Candies Among Children IIMedium2930Number of Strings Which Can Be Rearranged to Contain SubstringMedium2954Count the Number of Infection SequencesHard2963Count the Number of Good PartitionsHard3116Kth Smallest Amount With Single Denomination CombinationHard3128Right TrianglesMedium3154Find Number of Ways to Reach the K-th StairHard3179Find the N-th Value After K SecondsMedium3250Find the Count of Monotonic Pairs IHard3251Find the Count of Monotonic Pairs IIHard3272Find the Count of Good IntegersHard3312Sorted GCD Pair QueriesHard3317Find the Number of Possible Ways for an EventHard3343Count Number of Balanced PermutationsHard3352Count K-Reducible Numbers Less Than NHard3395Subsequences with a Unique Middle Mode IHard3405Count the Number of Arrays with K Matching Adjacent ElementsHard3426Manhattan Distances of All Arrangements of PiecesHard3428Maximum and Minimum Sums of at Most Size K SubsequencesMedium3461Check If Digits Are Equal in String After Operations IEasy3463Check If Digits Are Equal in String After Operations IIHard3470Permutations IVHard3518Smallest Palindromic Rearrangement IIHard3539Find Sum of Array Product of Magical SequencesHard3577Count the Number of Computer Unlocking PermutationsMedium3621Number of Integers With Popcount-Depth Equal to K IHard
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