LeetCode----202. Happy Number(Java)

 package isHappy202;
 /*
  * 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.
  */

 public class Solution {
     /*
      * solution:
      * 1
      * 2-4-16-37-58-89-145-42-20-4
      * 3-9-81-65-61
      * 4
      * 5-25-29-85-89
      * 6-36-45-41-17-50
      * 7-49-97-130-10
      * 8-64-52-29
      * 9-81-65
      * so only 1 and 7 is "happy"
      */
     public static boolean isHappy(int n) {
         while(n/10>0){
             int sum=0;
             while(n/10>0){
                 sum+=Math.pow((n%10),2);
                 n=n/10;
             }
             sum+=Math.pow(n,2);
             n=sum;
         }
         if (n==1||n==7)
             return true;
         return false;
     }
     public static void main(String[] args) {
         // TODO Auto-generated method stub
         System.out.println(isHappy(23456));
     }
 }