Given an array consisting of n integers, find the contiguous subarray of given length k that has the maximum average value. And you need to output the maximum average value.
Example 1:
Input: [1,12,-5,-6,50,3], k = 4 Output: 12.75 Explanation: Maximum average is (12-5-6+50)/4 = 51/4 = 12.75
Note:
k <= n <= 30,000.
struct Solution;
impl Solution {
fn find_max_average(nums: Vec<i32>, k: i32) -> f64 {
let mut sum = 0;
let k = k as usize;
let n = nums.len();
for i in 0..k {
sum += nums[i];
}
let mut max = sum;
for i in k..n {
sum += nums[i];
sum -= nums[i - k];
max = i32::max(sum, max);
}
max as f64 / k as f64
}
}
#[test]
fn test() {
use assert_approx_eq::assert_approx_eq;
let nums = vec![1, 12, -5, -6, 50, 3];
let k = 4;
assert_approx_eq!(Solution::find_max_average(nums, k), 12.75);
}