Leetcode

Prefix Sum + Hash Map

525.Contiguous Array
930.Binary Subarrays With Sum
974.Subarray Sums Divisible by K
1371.Find the Longest Substring Containing Vowels in Even Counts
1442.Count Triplets That Can Form Two Arrays of Equal XOR
1524.Number of Sub-arrays With Odd Sum
1542.Find Longest Awesome Substring
1590.Make Sum Divisible by P
1915.Number of Wonderful Substrings
1983.Widest Pair of Indices With Equal Range Sum
2025.Maximum Number of Ways to Partition an Array 2488.Count Subarrays With Median K
2489.Number of Substrings With Fixed Ratio
2845.Count of Interesting Subarrays
2875.Minimum Size Subarray in Infinite Array\

Greedy

Three Pass

1525.Number of Good Ways to Split a String
1653.Minimum Deletions to Make String Balanced
1664.Ways to Make a Fair Array
2874.Maximum Value of an Ordered Triplet II\

Binary Search

81.Search in Rotated Sorted Array II
215.Kth-Largest-Element-in-an-Array
373.Find-K-Pairs-with-Smallest-Sums
378.Kth-Smallest-Element-in-a-Sorted-Matrix
786.K-th Smallest-Prime-Fraction
1439.Find-the-Kth-Smallest-Sum-of-a-Matrix-With-Sorted-Rows
1482.Minimum-Number-of-Days-to-Make-m-Bouquets
1631.Path-With-Minimum-Effort
1870.Minimum Speed to Arrive on Time
1918.Kth-Smallest-Subarray-Sum
2040.Kth-Smallest-Product-of-Two-Sorted-Arrays
2226.Maximum-Candies-Allocated-to-K-Children

BFS (Including Topological Sort)

127.Word-Ladder
785.Is Graph Bipartite?
1162.As Far from Land as Possible
1462.Course Schedule IV

DFS

37.Sudoku Solver
473.Matchsticks to Square
491.Non-decreasing Subsequences
698.Partition to K Equal Sum Subsets
1306.Jump Game III
2597.The Number of Beautiful Subsets

Graph

743.Network Delay Time
1334.Find the City With the Smallest Number of Neighbors at a Threshold Distance

Monotonic Stack

42.Trapping Rain Water
84.Largest Rectangle in Histogram
85.Maximal Rectangle
496.Next Greater Element I
503.Next Greater Element II
768.Max Chunks To Make Sorted II
901.Online Stock Span
907.Sum of Subarray Minimums
962.Maximum Width Ramp
1063.Number of Valid Subarrays
1124.Longest Well-Performing Interval
1856.Maximum Subarray Min-Product
2104.Sum of Subarray Ranges
2334.Subarray With Elements Greater Than Varying Threshold
2355.Maximum Number of Books You Can Take
2434.Using a Robot to Print the Lexicographically Smallest String
2454.Next Greater Element IV
2866.Beautiful Towers II

Union Find

684.Redundant Connection
1489.Find Critical and Pseudo-Critical Edges in Minimum Spanning Tree
2867.Count Valid Paths in a Tree

Dynamic Programming

2355.Maximum Number of Books You Can Take