LeetCode-Pow(x, n)

Implement pow(x, n).

Solution:

Code:

<span style="font-size:14px;">class Solution {public:    double helper(double x, int n) {        if (n == 1) return x;        double temp = helper(x, n/2);        if (n%2) return temp*temp*x;        else return temp*temp;    }        double pow(double x, int n) {        if (x == 1) return 1;        if (x == -1) return n%2?-1:1;        if (n == 0) return 1;        if (n < 0) return 1/helper(x, -n);        else return helper(x, n);    }};</span>