hash function

Repeated DNA Sequences

Solve Repeated DNA Sequences by sliding a length-10 window and tracking seen patterns with a hash set or bitmask.

Shortest Palindrome

The Shortest Palindrome problem asks to transform a string into a palindrome by adding characters at the beginning, with…

Encode and Decode TinyURL

Design a class that encodes and decodes URLs using a URL shortening approach based on hash tables and strings.

Subtree of Another Tree

Determine if one binary tree is an exact subtree of another by comparing structure and node values recursively.

Design HashSet

Implement a custom HashSet without built-in libraries using array scanning and hash lookup for efficient membership chec…

Design HashMap

Implement a custom HashMap from scratch using array scanning and hash lookup without built-in libraries for efficient ke…

Maximum Length of Repeated Subarray

Find the maximum length of a subarray that appears in both given integer arrays using dynamic programming.

Longest Duplicate Substring

Find the longest duplicated substring in a string using binary search, sliding window, and rolling hash techniques.

Longest Chunked Palindrome Decomposition

Solve the "Longest Chunked Palindrome Decomposition" problem by using dynamic programming and string manipulation techni…

Distinct Echo Substrings

Count the distinct non-empty substrings of a given string that can be formed as the concatenation of a string with itsel…

Longest Happy Prefix

Find the longest non-empty prefix of a string that also appears as its suffix, optimizing with rolling hash techniques.

Check If a String Contains All Binary Codes of Size K

Determine if every possible binary string of length k exists as a substring within a given binary string s efficiently u…

Longest Common Subpath

The Longest Common Subpath problem requires finding the longest subpath shared by all paths in a graph using binary sear…

Delete Duplicate Folders in System

Solve Delete Duplicate Folders in System by building a trie, serializing child subtrees, and deleting repeated non-empty…

Maximum Product of the Length of Two Palindromic Substrings

Find the maximum product of lengths of two non-overlapping odd-length palindromic substrings using string and rolling ha…

Find Substring With Given Hash Value

Locate the first substring of length k whose rolling hash matches the given hashValue using a sliding window approach.

Sum of Scores of Built Strings

Calculate the sum of scores of built strings by analyzing longest common prefixes with suffixes in a string using effici…

K Divisible Elements Subarrays

Count all distinct subarrays with at most k elements divisible by p using array scanning and hash lookup techniques effi…

Maximum Deletions on a String

Find the maximum number of deletions on a string using state transition dynamic programming and rolling hash techniques …

Find Beautiful Indices in the Given Array I

Identify all beautiful indices where substring a appears and a nearby substring b exists within distance k efficiently.

Find Beautiful Indices in the Given Array II

Find Beautiful Indices in the Given Array II challenges you to use binary search and string matching techniques.

Minimum Time to Revert Word to Initial State I

Determine the minimum seconds to revert a string to its original state using repeated prefix shifts of length k efficien…

Minimum Time to Revert Word to Initial State II

The problem asks to calculate the minimum time required to revert a string to its initial state using specific operation…

Number of Subarrays That Match a Pattern I

Count all subarrays in a given integer array that strictly follow a defined numeric pattern using rolling hash checks ef…