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
func myPow(x float64, n int) float64 {
res := 0.0
if n > 0 {
res = recursion(x, n)
} else {
res = 1.0 / recursion(x, -n)
}
return res
}
func recursion(x float64, n int) float64 {
if n == 0 {
return 1
}
if n == 1 {
return x
}
res := recursion(x*x, n/2)
if n%2 == 1 {
res *= x
}
return res
}