标签：
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
public class Solution {
public boolean isHappy(int n) {
Set<Integer> numberSet = new HashSet<Integer>();
while(n!=1){
if(!numberSet.add(n)){
return false;
}
char[] chars = String.valueOf(n).toCharArray();
int total = 0;
for(Character ch: chars){
total += Math.pow(Integer.parseInt(ch+""),2);
}
n = total;
}
return true;
}
}
标签：
原文地址：http://www.cnblogs.com/incrediblechangshuo/p/5503859.html
