leetcode-Happy Number

3/8/2017來源:ASP.NET技巧人氣:18710

Question:

Write an algorithm to determine if a number is “happy”.

A happy number is a number defined by the following PRocess: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not include 1. Those numbers for which this process ends in 1 are happy numbers.

Example: 19 is a happy number

12 + 92 = 82 82 + 22 = 68 62 + 82 = 100 12 + 02 + 02 = 1

Solution:

class Solution { public: bool isHappy(int n) { if(n == 0){ return false; } n = getNum(n); unordered_set<int> mset; while(mset.insert(n).second){ if(n == 1){ return true; } n = getNum(n); } return false; } int getNum(int n){ int res = 0; while(n){ int tmp = n % 10; res += tmp * tmp; n /= 10; } return res; } };

總結:

unordered_set的函數insert返回值中各個版本都不一致:

(1) pair



百人牛牛鱼丸游戏下载大全 快乐8怎么玩 四人麻将单机版大全 甘肃快3开奖结果全部 南宁麻将app下载 天天捕鸟破解版下载 上海时时乐开奖直播室 江苏7位数怎么中奖 内蒙古11选5走势 幸运赛车组二 宁夏11选5购彩平台