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
Note:
-100.0 < x < 100.0 n is a 32-bit signed integer, within the range [−231, 231 − 1] public static double myPow(double x, int n) { double result =1; if(n==0) return 1; if(n<0) { x = 1 / x; result = 1; n = -n; } for(int i = 0; i < n; i++) { result *= x; } return result; } public static double myPow1(double x, int n) { if(n==0) return 1; double ans = 1; for(int i = Math.abs(n);i>0;i =i>>1,x*=x) { if((i&1)==1) ans*=x; } return n>0?ans:1/ans; }