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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
• 这个用很简单的数学方法，就可以实现。

• bool isHappy(int n) {	int remainder ;	long int sum = 0;	int times = 0;	while (n != 1 && times < 100)//循环判断，这里有些不足，因为Leetcode的测试用例有的好变态，所以用的100...更正确的方法是用哈//希表，如果出现重复的sum，则不是happy number，哈希表则用是否超过最大整数来做终止判断。	do{			remainder = n % 10;			sum += remainder * remainder;		} while ((n = n / 10) > 0);		n = sum;		sum = 0;		times++;	}	if (n == 1)		return true;	else		return false;}

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