LeetCode – Refresh – Pow(x, n)

class Solution {
public:
    double pow(double x, int n) {
        bool sign = false;
        if (n < 0) {
            n = -n;
            sign = true;
        }
        double power = x, result = 1.0;
        while (n > 0) {
            if (n%2 == 1) {
                result *= power;
            }
            power *= power;
            n /= 2;
        }
        if (sign) return 1/result;
        return result;
    }
};