Robina Li

Given an array of positive integers nums and an integer k, return the number of contiguous subarrays where the product...

You are given an array prices where prices[i] is the price of a stock on day i. Find the maximum...

In an infinite chess board with coordinates from -infinity to +infinity, a knight starts at (0, 0). Return the minimum...

Implement a SnapshotArray that supports: SnapshotArray(int length) – initializes an array of the given length (all zeros) void set(index, val)...

Design a hit counter that counts the number of hits received in the past 5 minutes (300 seconds).

Given a binary tree, a node X is good if there is no node with a value greater than X...