Robina Li

Given an integer array nums and an integer k, find the maximum sum among all subarrays of length k that have all distinct elements. Return 0 if no such subarray...

Given a singly linked list, return a random node’s value. Each node must have an equal probability of being chosen.

Given a palindromic string palindrome, replace exactly one character to make it not a palindrome, and make the resulting string the lexicographically smallest possible. Return the result, or an empty...

You are given a 0-indexed integer array nums of length n. A split at index i is valid if the sum of the first i + 1 elements is greater...

You are given an integer array pref of size n. Find and return the array arr of size n that satisfies:

Given an m x n integer matrix, if an element is 0, set its entire row and column to 0. You must do it in place.

Given n nodes labeled 0 to n-1 and a list of undirected edges, determine if these edges form a valid tree.

Given an integer array nums where exactly two elements appear once and all other elements appear exactly twice, find the two elements that appear only once. Return them in any...

You are given n train rides with distances dist[i]. Each train departs at an integer hour, so you must wait until the next whole hour to board the next train...

Implement a thread-safe bounded blocking queue with the following methods: BoundedBlockingQueue(int capacity) – initialize with max capacity void enqueue(int element) – add element to the back; blocks if the queue...