LeetCode202——Happy Number快乐数

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

实现：
bool isHappy(int n) {
vector<int> result;
int val = getSquareSum(n);
while (val != 1) {
if (std::find(result.begin(), result.end(), val) != result.end()) {
return false;
}
result.push_back(val);
val = getSquareSum(val);
}
return true;
}
int getSquareSum(int n) {
int val = 0;
while (n) {
int rem = n%10;
val += rem*rem;
n = n / 10;
}
return val;
}