[백준] 20186 수 고르기 - Greedy / Java

• 문제 링크

20186번: 수 고르기

 

• 풀이 과정

 

• 풀이 코드

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        StringTokenizer st = new StringTokenizer(br.readLine());

        int n = Integer.parseInt(st.nextToken());
        int k = Integer.parseInt(st.nextToken());

        int[] arr = new int[n];

        st = new StringTokenizer(br.readLine());
        for (int i = 0; i < n; i++)
            arr[i] = Integer.parseInt(st.nextToken());

        Arrays.sort(arr);

        int sum = 0;
        for (int i = n - 1, j = 0; i >= n - k; i--, j++)
            sum += arr[i] - j;

        bw.write(String.valueOf(sum));
        bw.flush();
    }

}