A collection of LeetCode questions to ace the coding interview! - Created using LeetHub v2

LeetCode Topics

Math

0007-reverse-integer
0009-palindrome-number
0012-integer-to-roman
0029-divide-two-integers
0070-climbing-stairs
0168-excel-sheet-column-title
0171-excel-sheet-column-number
0202-happy-number
0231-power-of-two
0258-add-digits
0486-predict-the-winner
0628-maximum-product-of-three-numbers
0633-sum-of-square-numbers
0836-rectangle-overlap
0877-stone-game
1140-stone-game-ii
1401-circle-and-rectangle-overlapping
1406-stone-game-iii
1510-stone-game-iv
1563-stone-game-v
1621-number-of-sets-of-k-non-overlapping-line-segments
1872-stone-game-viii
1927-sum-game
1979-find-greatest-common-divisor-of-array
2029-stone-game-ix
2769-find-the-maximum-achievable-number
3014-minimum-number-of-pushes-to-type-word-i
3116-kth-smallest-amount-with-single-denomination-combination
3312-sorted-gcd-pair-queries
3336-find-the-number-of-subsequences-with-equal-gcd
3345-smallest-divisible-digit-product-i
3512-minimum-operations-to-make-array-sum-divisible-by-k
3513-number-of-unique-xor-triplets-i
3514-number-of-unique-xor-triplets-ii
3518-smallest-palindromic-rearrangement-ii
3524-find-x-value-of-array-i
3525-find-x-value-of-array-ii
3536-maximum-product-of-two-digits
3622-check-divisibility-by-digit-sum-and-product
3658-gcd-of-odd-and-even-sums
3700-number-of-zigzag-arrays-ii
3867-sum-of-gcd-of-formed-pairs
3870-count-commas-in-range
3871-count-commas-in-range-ii
3875-construct-uniform-parity-array-i
3876-construct-uniform-parity-array-ii

Array

0001-two-sum
0018-4sum
0053-maximum-subarray
0075-sort-colors
0108-convert-sorted-array-to-binary-search-tree
0118-pascals-triangle
0119-pascals-triangle-ii
0121-best-time-to-buy-and-sell-stock
0303-range-sum-query-immutable
0373-find-k-pairs-with-smallest-sums
0486-predict-the-winner
0628-maximum-product-of-three-numbers
0674-longest-continuous-increasing-subsequence
0697-degree-of-an-array
0704-binary-search
0744-find-smallest-letter-greater-than-target
0835-image-overlap
0877-stone-game
1140-stone-game-ii
1260-shift-2d-grid
1331-rank-transform-of-an-array
1386-cinema-seat-allocation
1406-stone-game-iii
1464-maximum-product-of-two-elements-in-an-array
1477-find-two-non-overlapping-sub-arrays-each-with-target-sum
1563-stone-game-v
1846-maximum-element-after-decreasing-and-rearranging
1872-stone-game-viii
1979-find-greatest-common-divisor-of-array
2029-stone-game-ix
2091-removing-minimum-and-maximum-from-array
2213-longest-substring-of-one-repeating-character
2948-make-lexicographically-smallest-array-by-swapping-elements
2958-length-of-longest-subarray-with-at-most-k-frequency
2996-smallest-missing-integer-greater-than-sequential-prefix-sum
3069-distribute-elements-into-two-arrays-i
3116-kth-smallest-amount-with-single-denomination-combination
3312-sorted-gcd-pair-queries
3336-find-the-number-of-subsequences-with-equal-gcd
3414-maximum-score-of-non-overlapping-intervals
3471-find-the-largest-almost-missing-integer
3483-unique-3-digit-even-numbers
3501-maximize-active-section-with-trade-ii
3512-minimum-operations-to-make-array-sum-divisible-by-k
3513-number-of-unique-xor-triplets-i
3514-number-of-unique-xor-triplets-ii
3524-find-x-value-of-array-i
3525-find-x-value-of-array-ii
3532-path-existence-queries-in-a-graph-i
3534-path-existence-queries-in-a-graph-ii
3568-minimum-moves-to-clean-the-classroom
3702-longest-subsequence-with-non-zero-bitwise-xor
3718-smallest-missing-multiple-of-k
3731-find-missing-elements
3737-count-subarrays-with-majority-element-i
3739-count-subarrays-with-majority-element-ii
3867-sum-of-gcd-of-formed-pairs
3875-construct-uniform-parity-array-i
3876-construct-uniform-parity-array-ii
3898-find-the-degree-of-each-vertex
3903-smallest-stable-index-i
3904-smallest-stable-index-ii
3925-concatenate-array-with-reverse

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0012-integer-to-roman
0202-happy-number
0242-valid-anagram
0697-degree-of-an-array
1331-rank-transform-of-an-array
1386-cinema-seat-allocation
1477-find-two-non-overlapping-sub-arrays-each-with-target-sum
1520-maximum-number-of-non-overlapping-substrings
2958-length-of-longest-subarray-with-at-most-k-frequency
2996-smallest-missing-integer-greater-than-sequential-prefix-sum
3016-minimum-number-of-pushes-to-type-word-ii
3090-maximum-length-substring-with-two-occurrences
3312-sorted-gcd-pair-queries
3471-find-the-largest-almost-missing-integer
3483-unique-3-digit-even-numbers
3518-smallest-palindromic-rearrangement-ii
3532-path-existence-queries-in-a-graph-i
3568-minimum-moves-to-clean-the-classroom
3718-smallest-missing-multiple-of-k
3720-lexicographically-smallest-permutation-greater-than-target
3731-find-missing-elements
3737-count-subarrays-with-majority-element-i
3739-count-subarrays-with-majority-element-ii

Binary Search

0633-sum-of-square-numbers
0704-binary-search
0744-find-smallest-letter-greater-than-target
1477-find-two-non-overlapping-sub-arrays-each-with-target-sum
3116-kth-smallest-amount-with-single-denomination-combination
3312-sorted-gcd-pair-queries
3414-maximum-score-of-non-overlapping-intervals
3501-maximize-active-section-with-trade-ii
3532-path-existence-queries-in-a-graph-i
3534-path-existence-queries-in-a-graph-ii

Union-Find

2685-count-the-number-of-complete-components
2948-make-lexicographically-smallest-array-by-swapping-elements
3532-path-existence-queries-in-a-graph-i

Graph Theory

2685-count-the-number-of-complete-components
3310-remove-methods-from-project
3532-path-existence-queries-in-a-graph-i
3534-path-existence-queries-in-a-graph-ii
3898-find-the-degree-of-each-vertex

Two Pointers

0018-4sum
0075-sort-colors
0202-happy-number
0344-reverse-string
0633-sum-of-square-numbers
2472-maximum-number-of-non-overlapping-palindrome-substrings
3302-find-the-lexicographically-smallest-valid-sequence
3534-path-existence-queries-in-a-graph-ii
3734-lexicographically-smallest-palindromic-permutation-greater-than-target
3867-sum-of-gcd-of-formed-pairs

Dynamic Programming

0022-generate-parentheses
0053-maximum-subarray
0070-climbing-stairs
0115-distinct-subsequences
0118-pascals-triangle
0119-pascals-triangle-ii
0121-best-time-to-buy-and-sell-stock
0338-counting-bits
0486-predict-the-winner
0877-stone-game
0940-distinct-subsequences-ii
1140-stone-game-ii
1406-stone-game-iii
1477-find-two-non-overlapping-sub-arrays-each-with-target-sum
1510-stone-game-iv
1563-stone-game-v
1621-number-of-sets-of-k-non-overlapping-line-segments
1872-stone-game-viii
2472-maximum-number-of-non-overlapping-palindrome-substrings
3302-find-the-lexicographically-smallest-valid-sequence
3336-find-the-number-of-subsequences-with-equal-gcd
3414-maximum-score-of-non-overlapping-intervals
3524-find-x-value-of-array-i
3534-path-existence-queries-in-a-graph-ii
3699-number-of-zigzag-arrays-i
3700-number-of-zigzag-arrays-ii

Greedy

1081-smallest-subsequence-of-distinct-characters
1386-cinema-seat-allocation
1520-maximum-number-of-non-overlapping-substrings
1846-maximum-element-after-decreasing-and-rearranging
1927-sum-game
2029-stone-game-ix
2091-removing-minimum-and-maximum-from-array
2472-maximum-number-of-non-overlapping-palindrome-substrings
3014-minimum-number-of-pushes-to-type-word-i
3016-minimum-number-of-pushes-to-type-word-ii
3302-find-the-lexicographically-smallest-valid-sequence
3534-path-existence-queries-in-a-graph-ii
3720-lexicographically-smallest-permutation-greater-than-target

Bit Manipulation

0029-divide-two-integers
0190-reverse-bits
0191-number-of-1-bits
0231-power-of-two
0338-counting-bits
1386-cinema-seat-allocation
3116-kth-smallest-amount-with-single-denomination-combination
3513-number-of-unique-xor-triplets-i
3514-number-of-unique-xor-triplets-ii
3534-path-existence-queries-in-a-graph-ii
3568-minimum-moves-to-clean-the-classroom
3702-longest-subsequence-with-non-zero-bitwise-xor

Sorting

0018-4sum
0075-sort-colors
0242-valid-anagram
0628-maximum-product-of-three-numbers
1331-rank-transform-of-an-array
1464-maximum-product-of-two-elements-in-an-array
1520-maximum-number-of-non-overlapping-substrings
1846-maximum-element-after-decreasing-and-rearranging
2948-make-lexicographically-smallest-array-by-swapping-elements
2996-smallest-missing-integer-greater-than-sequential-prefix-sum
3016-minimum-number-of-pushes-to-type-word-ii
3414-maximum-score-of-non-overlapping-intervals
3517-smallest-palindromic-rearrangement-i
3534-path-existence-queries-in-a-graph-ii
3536-maximum-product-of-two-digits
3731-find-missing-elements
3867-sum-of-gcd-of-formed-pairs

String

0003-longest-substring-without-repeating-characters
0012-integer-to-roman
0022-generate-parentheses
0115-distinct-subsequences
0168-excel-sheet-column-title
0171-excel-sheet-column-number
0242-valid-anagram
0257-binary-tree-paths
0344-reverse-string
0940-distinct-subsequences-ii
1081-smallest-subsequence-of-distinct-characters
1520-maximum-number-of-non-overlapping-substrings
1927-sum-game
2213-longest-substring-of-one-repeating-character
2472-maximum-number-of-non-overlapping-palindrome-substrings
2904-shortest-and-lexicographically-smallest-beautiful-string
3014-minimum-number-of-pushes-to-type-word-i
3016-minimum-number-of-pushes-to-type-word-ii
3090-maximum-length-substring-with-two-occurrences
3302-find-the-lexicographically-smallest-valid-sequence
3498-reverse-degree-of-a-string
3499-maximize-active-section-with-trade-i
3501-maximize-active-section-with-trade-ii
3517-smallest-palindromic-rearrangement-i
3518-smallest-palindromic-rearrangement-ii
3720-lexicographically-smallest-permutation-greater-than-target
3734-lexicographically-smallest-palindromic-permutation-greater-than-target

Depth-First Search

0094-binary-tree-inorder-traversal
0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0111-minimum-depth-of-binary-tree
0112-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0226-invert-binary-tree
0257-binary-tree-paths
2265-count-nodes-equal-to-average-of-subtree
2685-count-the-number-of-complete-components
3310-remove-methods-from-project

Breadth-First Search

0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0111-minimum-depth-of-binary-tree
0112-path-sum
0226-invert-binary-tree
2685-count-the-number-of-complete-components
3310-remove-methods-from-project
3568-minimum-moves-to-clean-the-classroom

Enumeration

1291-sequential-digits
3345-smallest-divisible-digit-product-i
3483-unique-3-digit-even-numbers
3499-maximize-active-section-with-trade-i
3514-number-of-unique-xor-triplets-ii
3720-lexicographically-smallest-permutation-greater-than-target
3734-lexicographically-smallest-palindromic-permutation-greater-than-target

Number Theory

0258-add-digits
1979-find-greatest-common-divisor-of-array
3116-kth-smallest-amount-with-single-denomination-combination
3312-sorted-gcd-pair-queries
3336-find-the-number-of-subsequences-with-equal-gcd
3658-gcd-of-odd-and-even-sums
3867-sum-of-gcd-of-formed-pairs

Simulation

0258-add-digits
1260-shift-2d-grid
3069-distribute-elements-into-two-arrays-i
3498-reverse-degree-of-a-string
3867-sum-of-gcd-of-formed-pairs
3925-concatenate-array-with-reverse

Combinatorics

1621-number-of-sets-of-k-non-overlapping-line-segments
3116-kth-smallest-amount-with-single-denomination-combination
3312-sorted-gcd-pair-queries
3518-smallest-palindromic-rearrangement-ii

Counting

2029-stone-game-ix
3016-minimum-number-of-pushes-to-type-word-ii
3312-sorted-gcd-pair-queries
3518-smallest-palindromic-rearrangement-ii
3720-lexicographically-smallest-permutation-greater-than-target
3737-count-subarrays-with-majority-element-i

Prefix Sum

0303-range-sum-query-immutable
1140-stone-game-ii
1621-number-of-sets-of-k-non-overlapping-line-segments
1872-stone-game-viii
3312-sorted-gcd-pair-queries
3699-number-of-zigzag-arrays-i
3737-count-subarrays-with-majority-element-i
3739-count-subarrays-with-majority-element-ii
3903-smallest-stable-index-i
3904-smallest-stable-index-ii

Divide and Conquer

0053-maximum-subarray
0108-convert-sorted-array-to-binary-search-tree
0190-reverse-bits
0191-number-of-1-bits
3737-count-subarrays-with-majority-element-i
3739-count-subarrays-with-majority-element-ii

Stack

0094-binary-tree-inorder-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0225-implement-stack-using-queues
1081-smallest-subsequence-of-distinct-characters

Monotonic Stack

1081-smallest-subsequence-of-distinct-characters

Matrix

0835-image-overlap
1260-shift-2d-grid
3568-minimum-moves-to-clean-the-classroom
3898-find-the-degree-of-each-vertex

Segment Tree

2213-longest-substring-of-one-repeating-character
3501-maximize-active-section-with-trade-ii
3525-find-x-value-of-array-ii
3737-count-subarrays-with-majority-element-i
3739-count-subarrays-with-majority-element-ii

Merge Sort

3737-count-subarrays-with-majority-element-i
3739-count-subarrays-with-majority-element-ii

Heap (Priority Queue)

0373-find-k-pairs-with-smallest-sums
1464-maximum-product-of-two-elements-in-an-array

Counting Sort

3517-smallest-palindromic-rearrangement-i

Recursion

0203-remove-linked-list-elements
0206-reverse-linked-list
0231-power-of-two
0486-predict-the-winner
3483-unique-3-digit-even-numbers

Game Theory

0486-predict-the-winner
0877-stone-game
1140-stone-game-ii
1406-stone-game-iii
1510-stone-game-iv
1563-stone-game-v
1872-stone-game-viii
1927-sum-game
2029-stone-game-ix

Memoization

0070-climbing-stairs

Linked List

0203-remove-linked-list-elements
0206-reverse-linked-list
2058-find-the-minimum-and-maximum-number-of-nodes-between-critical-points

Sliding Window

0003-longest-substring-without-repeating-characters
1477-find-two-non-overlapping-sub-arrays-each-with-target-sum
2904-shortest-and-lexicographically-smallest-beautiful-string
2958-length-of-longest-subarray-with-at-most-k-frequency
3090-maximum-length-substring-with-two-occurrences

Minimax

1140-stone-game-ii
1510-stone-game-iv
1872-stone-game-viii
2029-stone-game-ix

Zero-Sum Game

1140-stone-game-ii
1510-stone-game-iv
1872-stone-game-viii
2029-stone-game-ix

Nim Game

1510-stone-game-iv
2029-stone-game-ix

Sprague–Grundy Theorem

1510-stone-game-iv

Ordered Set

2213-longest-substring-of-one-repeating-character

Tree

0094-binary-tree-inorder-traversal
0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0108-convert-sorted-array-to-binary-search-tree
0110-balanced-binary-tree
0111-minimum-depth-of-binary-tree
0112-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0226-invert-binary-tree
0257-binary-tree-paths
2265-count-nodes-equal-to-average-of-subtree

Binary Tree

0094-binary-tree-inorder-traversal
0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0108-convert-sorted-array-to-binary-search-tree
0110-balanced-binary-tree
0111-minimum-depth-of-binary-tree
0112-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0226-invert-binary-tree
0257-binary-tree-paths
2265-count-nodes-equal-to-average-of-subtree

Binary Search Tree

0108-convert-sorted-array-to-binary-search-tree

Floyd's Cycle Finding Algorithm

0202-happy-number

Design

0225-implement-stack-using-queues
0303-range-sum-query-immutable

Queue

0225-implement-stack-using-queues

Geometry

0836-rectangle-overlap
1401-circle-and-rectangle-overlapping

Backtracking

0022-generate-parentheses
0257-binary-tree-paths

Bracket Sequences

0022-generate-parentheses