326. Power of Three
来源:互联网 发布:hack支付源码 编辑:程序博客网 时间:2024/06/06 06:49
题目来源【Leetcode】
Given an integer, write a function to determine if it is a power of three.
Follow up:
Could you do it without using any loop / recursion?
这道题要求不用循环来判断这个数是否为3的N次方
方法一: 用取对数的办法 n = 3^i;最后就是证明log10(n)/log10(3)是否为整数
class Solution {public: bool isPowerOfThree(int n) { double i = log10(n)/log10(3); return ((i-(int)i)== 0); }};
方法二:根据能够表示最大3的N次方的数来除n:
class Solution {public: bool isPowerOfThree(int n) { return n > 0 && 1162261467%n == 0 ; }};
阅读全文
0 0
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- 326. Power of Three
- Translate 【gcd 妙用】
- django 实现文件下载功能
- java web四大域对象
- Linux_入门基础
- 10多岁比智力,20多岁比体力,30来岁拼专业,40岁拼人脉
- 326. Power of Three
- shader初步之ShaderLab语法
- webpack的安装步鄹,对于小白易懂!
- ArrayDeque
- git教程
- 最短距离模板
- 代理服务器(Proxy Server)与网络地址转换(NAT)
- 从零开始学习laravel web(五)
- 【数据结构】红黑树详解