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

LeetCode Topics

Array

0001-two-sum
0014-longest-common-prefix
0027-remove-element
0035-search-insert-position
0053-maximum-subarray
0066-plus-one
0075-sort-colors
0121-best-time-to-buy-and-sell-stock
0152-maximum-product-subarray
0169-majority-element
0486-predict-the-winner
0628-maximum-product-of-three-numbers
0835-image-overlap
0877-stone-game
1288-remove-covered-intervals
1301-number-of-paths-with-max-score
1331-rank-transform-of-an-array
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
1658-minimum-operations-to-reduce-x-to-zero
1872-stone-game-viii
1979-find-greatest-common-divisor-of-array
2029-stone-game-ix
2149-rearrange-array-elements-by-sign
2213-longest-substring-of-one-repeating-character
2267-check-if-there-is-a-valid-parentheses-string-path
2333-minimum-sum-of-squared-difference
2778-sum-of-squares-of-special-elements
2897-apply-operations-on-array-to-maximize-sum-of-squares
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
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
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
3550-smallest-index-with-digit-sum-equal-to-index
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
3867-sum-of-gcd-of-formed-pairs
3875-construct-uniform-parity-array-i
3876-construct-uniform-parity-array-ii
3903-smallest-stable-index-i
3904-smallest-stable-index-ii

Dynamic Programming

0022-generate-parentheses
0032-longest-valid-parentheses
0053-maximum-subarray
0115-distinct-subsequences
0121-best-time-to-buy-and-sell-stock
0152-maximum-product-subarray
0486-predict-the-winner
0678-valid-parenthesis-string
0877-stone-game
0940-distinct-subsequences-ii
1301-number-of-paths-with-max-score
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
2267-check-if-there-is-a-valid-parentheses-string-path
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

Hash Table

0001-two-sum
0169-majority-element
0205-isomorphic-strings
0242-valid-anagram
0451-sort-characters-by-frequency
1096-brace-expansion-ii
1331-rank-transform-of-an-array
1477-find-two-non-overlapping-sub-arrays-each-with-target-sum
1520-maximum-number-of-non-overlapping-substrings
1658-minimum-operations-to-reduce-x-to-zero
2897-apply-operations-on-array-to-maximize-sum-of-squares
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
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

Two Pointers

0027-remove-element
0075-sort-colors
2149-rearrange-array-elements-by-sign
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

Sorting

0075-sort-colors
0169-majority-element
0242-valid-anagram
0451-sort-characters-by-frequency
0628-maximum-product-of-three-numbers
1096-brace-expansion-ii
1288-remove-covered-intervals
1331-rank-transform-of-an-array
1464-maximum-product-of-two-elements-in-an-array
1520-maximum-number-of-non-overlapping-substrings
2333-minimum-sum-of-squared-difference
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

Divide and Conquer

0053-maximum-subarray
0169-majority-element
0190-reverse-bits

Counting

0169-majority-element
0451-sort-characters-by-frequency
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

Simulation

2149-rearrange-array-elements-by-sign
3498-reverse-degree-of-a-string
3867-sum-of-gcd-of-formed-pairs

Math

0002-add-two-numbers
0066-plus-one
0486-predict-the-winner
0628-maximum-product-of-three-numbers
0836-rectangle-overlap
0877-stone-game
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
1979-find-greatest-common-divisor-of-array
2029-stone-game-ix
3014-minimum-number-of-pushes-to-type-word-i
3312-sorted-gcd-pair-queries
3336-find-the-number-of-subsequences-with-equal-gcd
3345-smallest-divisible-digit-product-i
3348-smallest-divisible-digit-product-ii
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
3550-smallest-index-with-digit-sum-equal-to-index
3622-check-divisibility-by-digit-sum-and-product
3658-gcd-of-odd-and-even-sums
3754-concatenate-non-zero-digits-and-multiply-by-sum-i
3756-concatenate-non-zero-digits-and-multiply-by-sum-ii
3867-sum-of-gcd-of-formed-pairs
3871-count-commas-in-range-ii
3875-construct-uniform-parity-array-i
3876-construct-uniform-parity-array-ii

Number Theory

1979-find-greatest-common-divisor-of-array
3312-sorted-gcd-pair-queries
3336-find-the-number-of-subsequences-with-equal-gcd
3348-smallest-divisible-digit-product-ii
3658-gcd-of-odd-and-even-sums
3867-sum-of-gcd-of-formed-pairs

Bit Manipulation

0190-reverse-bits
2897-apply-operations-on-array-to-maximize-sum-of-squares
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

String

0014-longest-common-prefix
0020-valid-parentheses
0022-generate-parentheses
0032-longest-valid-parentheses
0115-distinct-subsequences
0205-isomorphic-strings
0242-valid-anagram
0301-remove-invalid-parentheses
0451-sort-characters-by-frequency
0678-valid-parenthesis-string
0856-score-of-parentheses
0921-minimum-add-to-make-parentheses-valid
0940-distinct-subsequences-ii
1081-smallest-subsequence-of-distinct-characters
1096-brace-expansion-ii
1111-maximum-nesting-depth-of-two-valid-parentheses-strings
1190-reverse-substrings-between-each-pair-of-parentheses
1520-maximum-number-of-non-overlapping-substrings
1541-minimum-insertions-to-balance-a-parentheses-string
1614-maximum-nesting-depth-of-the-parentheses
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
3302-find-the-lexicographically-smallest-valid-sequence
3348-smallest-divisible-digit-product-ii
3498-reverse-degree-of-a-string
3499-maximize-active-section-with-trade-i
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
3756-concatenate-non-zero-digits-and-multiply-by-sum-ii

Heap (Priority Queue)

0451-sort-characters-by-frequency
1464-maximum-product-of-two-elements-in-an-array
2333-minimum-sum-of-squared-difference

Bucket Sort

0451-sort-characters-by-frequency

Stack

0020-valid-parentheses
0032-longest-valid-parentheses
0678-valid-parenthesis-string
0856-score-of-parentheses
0921-minimum-add-to-make-parentheses-valid
1081-smallest-subsequence-of-distinct-characters
1096-brace-expansion-ii
1111-maximum-nesting-depth-of-two-valid-parentheses-strings
1190-reverse-substrings-between-each-pair-of-parentheses
1541-minimum-insertions-to-balance-a-parentheses-string
1614-maximum-nesting-depth-of-the-parentheses

Binary Search

0035-search-insert-position
1477-find-two-non-overlapping-sub-arrays-each-with-target-sum
1658-minimum-operations-to-reduce-x-to-zero
2333-minimum-sum-of-squared-difference
3312-sorted-gcd-pair-queries
3414-maximum-score-of-non-overlapping-intervals
3532-path-existence-queries-in-a-graph-i
3534-path-existence-queries-in-a-graph-ii

Combinatorics

1621-number-of-sets-of-k-non-overlapping-line-segments
3312-sorted-gcd-pair-queries
3518-smallest-palindromic-rearrangement-ii

Prefix Sum

1621-number-of-sets-of-k-non-overlapping-line-segments
1658-minimum-operations-to-reduce-x-to-zero
1872-stone-game-viii
3312-sorted-gcd-pair-queries
3756-concatenate-non-zero-digits-and-multiply-by-sum-ii
3903-smallest-stable-index-i
3904-smallest-stable-index-ii

Enumeration

1291-sequential-digits
2778-sum-of-squares-of-special-elements
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

Greedy

0678-valid-parenthesis-string
0921-minimum-add-to-make-parentheses-valid
1081-smallest-subsequence-of-distinct-characters
1520-maximum-number-of-non-overlapping-substrings
1541-minimum-insertions-to-balance-a-parentheses-string
2029-stone-game-ix
2333-minimum-sum-of-squared-difference
2472-maximum-number-of-non-overlapping-palindrome-substrings
2897-apply-operations-on-array-to-maximize-sum-of-squares
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
3348-smallest-divisible-digit-product-ii
3534-path-existence-queries-in-a-graph-ii
3720-lexicographically-smallest-permutation-greater-than-target

Monotonic Stack

1081-smallest-subsequence-of-distinct-characters

Counting Sort

3517-smallest-palindromic-rearrangement-i

Linked List

0002-add-two-numbers
2058-find-the-minimum-and-maximum-number-of-nodes-between-critical-points

Recursion

0002-add-two-numbers
0486-predict-the-winner
3483-unique-3-digit-even-numbers

Game Theory

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

Minimax

1406-stone-game-iii
1510-stone-game-iv
1872-stone-game-viii
2029-stone-game-ix

Zero-Sum Game

1406-stone-game-iii
1510-stone-game-iv
1872-stone-game-viii
2029-stone-game-ix

Trie

0014-longest-common-prefix

Depth-First Search

2265-count-nodes-equal-to-average-of-subtree
2685-count-the-number-of-complete-components
3310-remove-methods-from-project

Breadth-First Search

0301-remove-invalid-parentheses
1096-brace-expansion-ii
2685-count-the-number-of-complete-components
3310-remove-methods-from-project
3568-minimum-moves-to-clean-the-classroom

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

Backtracking

0022-generate-parentheses
0301-remove-invalid-parentheses
1096-brace-expansion-ii
3348-smallest-divisible-digit-product-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

Nim Game

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

Sprague–Grundy Theorem

1510-stone-game-iv

Sliding Window

1477-find-two-non-overlapping-sub-arrays-each-with-target-sum
1658-minimum-operations-to-reduce-x-to-zero
2904-shortest-and-lexicographically-smallest-beautiful-string
2958-length-of-longest-subarray-with-at-most-k-frequency

Segment Tree

2213-longest-substring-of-one-repeating-character
3525-find-x-value-of-array-ii

Ordered Set

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

Matrix

0835-image-overlap
1301-number-of-paths-with-max-score
2267-check-if-there-is-a-valid-parentheses-string-path
3568-minimum-moves-to-clean-the-classroom

Tree

2265-count-nodes-equal-to-average-of-subtree

Binary Tree

2265-count-nodes-equal-to-average-of-subtree

Geometry

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

Bracket Sequences

0020-valid-parentheses
0022-generate-parentheses
0032-longest-valid-parentheses
0678-valid-parenthesis-string
0856-score-of-parentheses
0921-minimum-add-to-make-parentheses-valid
1111-maximum-nesting-depth-of-two-valid-parentheses-strings
1190-reverse-substrings-between-each-pair-of-parentheses
1541-minimum-insertions-to-balance-a-parentheses-string
2267-check-if-there-is-a-valid-parentheses-string-path