leetcode-Java-202. Happy Number

public class Solution {
public boolean isHappy(int n) {
int m = 0;

if(n == 1 || n == 7) {
return true;
}
if(n < 10) {
return false;
}
while(n > 0) {
m += (n % 10) * (n % 10);
n = n/10;
}
return isHappy(m);
}
}