leetcode50.cpp

class Solution {
public:
    double myPow(double x, int n) {
        if(n == 0) 
        	return 1;
        if(n == 1)
        	return x;
        if(x == 0)
            return 0;
        if(n < 0)
        {
        	n = -n;
        	x = 1/x;
        }
        return (n%2 == 0)? pow(x*x,n/2) : x*pow(x*x,n/2);
    }
};