摘要：
给你一个整数数组 nums ，除某个元素仅出现 一次 外，其余每个元素都恰出现 三次 。请你找出并返回那个只出现了一次的元素。 示例 1： 输入：nums = [2,2,3,2] 输出：3 示例 2： 输入：nums = [0,1,0,1,0,1,99] 输出：99 提示： 1 ⇐ nums.len 阅读全文
摘要：
You are given two integer arrays a and b of length n. You can reverse at most one subarray (continuous subsegment) of the array 𝑎a. Your task is to r 阅读全文
摘要：
Polycarp is an organizer of a Berland ICPC regional event. There are 𝑛n universities in Berland numbered from 1 to n. Polycarp knows all competitive 阅读全文
摘要：
There is a n×m grid. You are standing at cell (1,1) and your goal is to finish at cell (n,m). You can move to the neighboring cells to the right or do 阅读全文
摘要：
You have r red and b blue beans. You'd like to distribute them among several (maybe, one) packets in such a way that each packet: has at least one red 阅读全文