明明感覺自己做的出來卻花了好多時間沒有半點想法 最後還是看了答案
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.
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.
Return true if n is a happy number, and false if not.
class Solution {
public:
int sumOfDigits(int n) {
int x = 0;
while(n > 0) {
x += (n % 10) * (n % 10);
n /= 10;
}
return x;
}
bool isHappy(int n) {
while(n > 4) {
n = sumOfDigits(n);
}
return n == 1;
}
};