133. Clone Graph
Problem Given a reference of a node in a connected undirected graph. Return a deep copy (clone) of the graph. Each node in th...
5. Longest Palindromic Substring
Problem Given a string s, return the longest palindromic substring in s. A string is palindromic if it reads the same forwar...
540. Single Element in a Sorted Array
Problem You are given a sorted array consisting of only integers where every element appears exactly twice, except for one el...
3. Longest Substring Without Repeating Characters
Problem Given a string s, find the length of the longest substring without repeating characters. A substring is a contiguous...
3242. Design Neighbor Sum Service
Problem You are given a n x n 2D array grid containing distinct elements in the range [0, n² - 1]. Implement the NeighborSum ...
1. Two Sum
Problem Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to tar...
128. Longest Consecutive Sequence
Problem Given an unsorted array of integers nums, return the length of the longest consecutive elements sequence. You must wr...
3235. Check if the Rectangle Corner Is Reachable
Problem You are given two positive integers xCorner and yCorner, and a 2D array circles, where circles[i] = [xᵢ, yᵢ, rᵢ] deno...