leetcode——202——Happy Number

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) {
if(n<=0) return false;

map<int,bool> map;

while(1)
{
int sum = 0;
while(n)
{
int data = n%10;
n/=10;
sum += data*data;
}

if(sum==1) return true;

if(map[sum]==true)  return false;

map[sum]=true;

n = sum;

}

return false;

}
};