import java.util.*;
 
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        int[] a = new int[n];
        for(int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
 
        // 初始等待时间是 a[1] 到 a[n-1] 的和（不包括第1首歌）
        long totalWait = 0;
        for(int i = 1; i < n; i++) {
            totalWait += a[i];
        }
 
        // 提取第2首歌之后的 n-1 首，排序后去掉最大的 k 个
        Integer[] rest = new Integer[n - 1];
        for(int i = 1; i < n; i++) {
            rest[i - 1] = a[i];
        }
        Arrays.sort(rest, Collections.reverseOrder()); // 降序
 
        for(int i = 0; i < k; i++) {
            totalWait -= rest[i]; // 移除最长的 k 首
        }
 
        System.out.println(totalWait);
    }
}
 

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

MyAxCjEgMiAz

3 1
1 2 3