[백준] 11508 2+1 세일 - Greedy / Java

• 문제 링크

11508번: 2+1 세일

 

• 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.Comparator;

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));

        int n = Integer.parseInt(br.readLine());

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

        Arrays.sort(arr, Comparator.reverseOrder());

        int sum = 0;
        for (int i = 0; i < n; i++) {
            if (i % 3 == 2)
                continue;
            sum += arr[i];
        }

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

}