README.md

2611. Mice and Cheese

There are two mice and n different types of cheese, each type of cheese should be eaten by exactly one mouse.

A point of the cheese with index i (0-indexed) is:

• reward1[i] if the first mouse eats it.
• reward2[i] if the second mouse eats it.

You are given a positive integer array reward1, a positive integer array reward2, and a non-negative integer k.

Return the maximum points the mice can achieve if the first mouse eats exactly k types of cheese.

Example 1:

Input: reward1 = [1,1,3,4], reward2 = [4,4,1,1], k = 2
Output: 15
Explanation: In this example, the first mouse eats the 2nd (0-indexed) and the 3rd types of cheese, and the second mouse eats the 0th and the 1st types of cheese.
The total points are 4 + 4 + 3 + 4 = 15.
It can be proven that 15 is the maximum total points that the mice can achieve.

Example 2:

Input: reward1 = [1,1], reward2 = [1,1], k = 2
Output: 2
Explanation: In this example, the first mouse eats the 0th (0-indexed) and 1st types of cheese, and the second mouse does not eat any cheese.
The total points are 1 + 1 = 2.
It can be proven that 2 is the maximum total points that the mice can achieve.

Constraints:

• 1 <= n == reward1.length == reward2.length <= 105
• 1 <= reward1[i], reward2[i] <= 1000
• 0 <= k <= n

Solutions (Rust)

1. Solution

impl Solution {
    pub fn mice_and_cheese(reward1: Vec<i32>, reward2: Vec<i32>, k: i32) -> i32 {
        let mut indices = (0..reward1.len()).collect::<Vec<_>>();
        let mut ret = 0;

        indices.sort_unstable_by_key(|&i| reward2[i] - reward1[i]);

        for i in 0..reward1.len() {
            if i < k as usize {
                ret += reward1[indices[i]];
            } else {
                ret += reward2[indices[i]];
            }
        }

        ret
    }
}