Question
Implement pow(x, n), which calculates x raised to the power n (xn).
Example 1:
Input: 2.00000, 10
Output: 1024.00000
Example 2:
Input: 2.10000, 3
Output: 9.26100
Example 3:
Input: 2.00000, -2
Output: 0.25000
Explanation: 2-2 = 1/22 = 1/4 = 0.25
Solution
TODO
Code
class Solution {
public double myPow(double x, int n) {
if(n==0) return 1;
if(n==1) return x;
if(n==-1) return 1/x;
double res = myPow(x*x, n/2);
if(n>0 && n%2==1) res *= x;
if(n<0 && (-n)%2==1) res *= 1/x;
return res;
}
}
Performance
TODO