快乐数--双指针
一:题目
题目链接:. - 力扣(LeetCode)
二:算法原理
三:代码编写
int Sum(int n)
{
int sum = 0;
while(n)
{
sum += pow(n%10,2);
n /= 10;
}
return sum;
}
bool isHappy(int n)
{
int slow = n,fast = Sum(n);
while(slow != fast)
{
slow = Sum(slow);
fast = Sum(Sum(fast));
}
return slow == 1;
}