[BOJ] 13164 행복 유치원 (JAVA)

https://www.acmicpc.net/problem/13164

13164번: 행복 유치원

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Comparator;
import java.util.PriorityQueue;
import java.util.StringTokenizer;

public class Main {
	
    public static void main(String[] args) throws Exception {

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine(), " ");
        int N = Integer.parseInt(st.nextToken());
        int K = Integer.parseInt(st.nextToken());
        if (N == K) {
            System.out.print(0);
            return;
        }
        int[] input = new int[N];
        PriorityQueue<Integer> pq = new PriorityQueue<>(Comparator.reverseOrder());
        st = new StringTokenizer(br.readLine(), " ");
        for (int i = 0; i < N; i++) {
            input[i] = Integer.parseInt(st.nextToken());
        } // end of input

        for (int i = 1; i < N; i++) {
            pq.offer(input[i] - input[i - 1]);
        }

        int sum = input[N - 1] - input[0];
        for (int i = 1; i < K; i++) {
            sum -= pq.poll();
        }

        System.out.print(sum);

    }
	
}