Leetcode pow(x,n) solution

 50. Pow(x, n)

Medium

Implement pow(x, n), which calculates x raised to the power n (i.e., xn).

 

Example 1:

Input: x = 2.00000, n = 10
Output: 1024.00000

Example 2:

Input: x = 2.10000, n = 3
Output: 9.26100

Example 3:

Input: x = 2.00000, n = -2
Output: 0.25000
Explanation: 2-2 = 1/22 = 1/4 = 0.25

 

Constraints:

• -100.0 < x < 100.0
• -231 <= n <= 231-1
• -104 <= xn <= 104

Practice Here :

(8) Pow(x, n) - LeetCode

Solution :

class Solution {

public:

    double myPow2(double x,long long int n) {

        if(n==0||x==1)

            return 1;

        else if(n==1)

            return x;

        else if(n<0)

        {

            return 1/myPow2(x,n/-1);

        }

        else if(n%2==0)

            return myPow2(x*x,n/2);

        else return myPow2(x*x,n/2)*x;

    }

    double myPow(double x, int n) {

        return myPow2(x,n);

    }

};