At the beginning of every day, the first person who signs in the computer room will unlock the door, and the last one who signs out will lock the door. Given the records of signing in's and out's, you are supposed to find the ones who have unlocked a…
点我阅读原文 最近利用闲暇时间做了一下 PTA Basic Level[1] 里的题,里面现在一共有 95 道题,这些题大部分很基础,对于刷倦了 leetcode 的小伙伴可以去里面愉快的玩耍哦. 这里我挑了三个挺有意思的题来做个简单记录,欢迎和大家一起讨论交流. 请听题: 第一题:1009 说反话 题目描述 给定一个英语句子,各个单词之间用空格分隔.要求你编写程序,将句中所有单词的顺序颠倒输出. 输入示例 Hello World Here I Come 输出示例 Come I Here Wor…
Reversible Primes A reversible prime in any number system is a prime whose "reverse" in that number system is also a prime. For example in the decimal system 73 is a reversible prime because its reverse 37 is also a prime. Now given any two posi…