Robina Li

We have n chips, where the position of the i-th chip is position[i].

Given an integer array nums of 2n integers, group these integers into n pairs (a1, b1), (a2, b2), ..., (an, bn) such that the sum of min(ai, bi) for all...

You are given an integer array prices where prices[i] is the price of a given stock on the i-th day.

Given two strings s and t, return true if s is a subsequence of t, or false otherwise.

You are given an integer array nums. You are initially positioned at the array’s first index, and each element in the array represents your maximum jump length at that position....

There are some spherical balloons taped onto a flat wall that represents the XY-plane. The balloons are represented as a 2D array points where points[i] = [xstart, xend] denotes a...

Given an array of intervals intervals where intervals[i] = [starti, endi], return the minimum number of intervals you need to remove to make the rest of the intervals non-overlapping.

At a lemonade stand, each lemonade costs 5. Customers are standing in a queue to buy from you and order one at a time (in the order specified by bills)....

Assume you are an awesome parent and want to give your children some cookies. But, you should give each child at most one cookie.

Android devices have a special lock screen with a 3 x 3 grid of dots. Users can set an “unlock pattern” by connecting the dots in a specific sequence, which...