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
class Solution { public: bool isHappy(int n) { map<int,int> value; while(n!=1) { value[n]=1; int remain; int tmp=0; while(n!=0) { remain=n%10; tmp+=remain*remain; n=n/10; } n=tmp; if(value.find(n)!=value.end()) break;//是否已经出现过 } if(n!=1) return false; return true; } };
时间: 2024-12-20 22:29:40