GuRenjie

Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.

On an **8×8** chessboard, there can be multiple Black Queens and one White King. Given an array of integer coordinates `queens` that represents the positions of the Black Queens, and a pair of coordinates `king` that represent the position of the White King, return the coordinates of all the queens (in any order) that can attack the King.

Given an array of integers `nums`, calculate the **pivot index** of this array. The **pivot index** is the index where the sum of all the numbers **strictly** to the left of the index is equal to the sum of all the numbers **strictly** to the index’s right. If the index is on the left edge of the array, then the left sum is `0` because there are no elements to the left. This also applies to the right edge of the array. Return *the **leftmost pivot index***. If no such index exists, return -1.

Given an array of non-negative integers nums, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Determine if you are able to reach the last index.

Given a binary string `s` (a string consisting only of ‘0’s and ‘1’s), we can split `s` into 3 non-empty strings s1, s2, s3 (s1+ s2+ s3 = s). Return the number of ways `s` can be split such that the number of characters ‘1’ is the same in s1, s2, and s3. Since the answer may be too large, return it modulo 10^9 + 7.

This post is just for testing. 烫烫烫屯屯屯