Pow(x, n)

Pow(x, n)

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

Examples

Example 1:

Input: x = 2.00000, n = 10
Output: 1024.00000
Explanation: 2^10 = 1024.

Example 2:

Input: x = 2.10000, n = 3
Output: 9.26100
Explanation: 2.1^3 = 9.261.

Example 3:

Input: x = 2.00000, n = -2
Output: 0.25000
Explanation: 2^(-2) = 1 / 2^2 = 1/4 = 0.25.

Constraints

• -100.0 < x < 100.0
• -2^31 <= n <= 2^31 - 1
• n is an integer
• Either x is not zero or n > 0
• -10^4 <= x^n <= 10^4

Expected Complexity

• Time: O(log n)
• Space: O(1)