50. Pow(x, n)

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

50. Pow(x, n)
struct Solution;

impl Solution {
    fn my_pow(x: f64, n: i32) -> f64 {
        x.powi(n)
    }
}

#[test]
fn test() {
    use assert_approx_eq::assert_approx_eq;
    assert_approx_eq!(Solution::my_pow(2.0, 10), 1024.0);
    assert_approx_eq!(Solution::my_pow(2.0, -3), 0.125);
    assert_approx_eq!(Solution::my_pow(1.0, -2_147_483_648), 1.0);
}