README.md

2439. Minimize Maximum of Array

You are given a 0-indexed array nums comprising of n non-negative integers.

In one operation, you must:

• Choose an integer i such that 1 <= i < n and nums[i] > 0.
• Decrease nums[i] by 1.
• Increase nums[i - 1] by 1.

Return the minimum possible value of the maximum integer of nums after performing any number of operations.

Example 1:

Input: nums = [3,7,1,6]
Output: 5
Explanation:
One set of optimal operations is as follows:
1. Choose i = 1, and nums becomes [4,6,1,6].
2. Choose i = 3, and nums becomes [4,6,2,5].
3. Choose i = 1, and nums becomes [5,5,2,5].
The maximum integer of nums is 5. It can be shown that the maximum number cannot be less than 5.
Therefore, we return 5.

Example 2:

Input: nums = [10,1]
Output: 10
Explanation:
It is optimal to leave nums as is, and since 10 is the maximum value, we return 10.

Constraints:

• n == nums.length
• 2 <= n <= 105
• 0 <= nums[i] <= 109

Solutions (Rust)

1. Solution

impl Solution {
    pub fn minimize_array_value(nums: Vec<i32>) -> i32 {
        let n = nums.len();
        let mut lo = *nums.iter().min().unwrap() as i64;
        let mut hi = *nums.iter().max().unwrap() as i64;

        while lo < hi {
            let m = (lo + hi) / 2;
            let mut x = nums[n - 1] as i64;

            for i in (1..n).rev() {
                if x > m {
                    x += nums[i - 1] as i64 - m;
                } else {
                    x = nums[i - 1] as i64;
                }
            }

            if x > m {
                lo = m + 1;
            } else {
                hi = m;
            }
        }

        hi as i32
    }
}