数值的整数次方

class Solution {
public:
    double Power(double base, int exponent) {
        double rt=1.0;
        int tmp=exponent;     
        
        if(exponent == 0 )return 1;
        if(exponent <0 ) tmp=(-exponent);
        
        for(int i=1;i<=tmp ;i++)
        {
            rt*=base;
        }
        
        if(exponent < 0 )
        {
            rt=(1/rt);
        }
        
        return rt;
    }
};