Happy Number
浏览数：24 /
时间：2015年06月11日
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
总体来说，还是比较好理解的，主要是怎么判断进入了一个死循环，以及求每个数字的平方和
<span style="font-size:18px;">public class Solution {
public boolean isHappy(int n) {
if(n == 0){
return false;
}
Set<Integer> set = new HashSet<Integer>();//存储平方和，判断是否进入了一个死循环
Queue<Integer> queue = new LinkedList<Integer>();//存储n分解出来的数字
while(n != 1){
if(set.contains(n)){
return false;//进入了一个circle
}else{
set.add(n);
}
while(n != 0){
queue.offer(n % 10);
n = n / 10;
}
n = 0;
while(queue.peek() != null){
int tmp = queue.poll();
n = n + tmp*tmp;
}
}
return true;
}
}</span>郑重声明：本站内容如果来自互联网及其他传播媒体，其版权均属原媒体及文章作者所有。转载目的在于传递更多信息及用于网络分享，并不代表本站赞同其观点和对其真实性负责，也不构成任何其他建议。
