小美的游戏（美团2024届秋招笔试第三场编程真题）

核心思想

贪心，每次选最大的两个~

代码

import java.util.*;

public class Main {
    public static void main(String[] args) {
        final long MOD = (long) (1e9 + 7);
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();
        Long[] nums = new Long[n];
        for(int i = 0; i < n; i++){
            nums[i] = scanner.nextLong();
        }
        Arrays.sort(nums);
        if(n > 1) {
            int idx = n - 2;
            for (int i = 0; i < m; i++) {
                long a = nums[idx];
                long b = nums[idx + 1];

                a = (a * b) % MOD;
                b = 1L;

                nums[idx] = a;
                nums[idx + 1] = b;
                idx --;
            }
        }
        long res = 0L;
        for(Long num : nums){
            res = (res + num) % MOD;
        }
        System.out.println(res);
    }
}