백준 11508

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

class Main11508 {

   public static void main(String[] args) throws Exception {
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

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

      List<Integer> C = new ArrayList<>(N);

      for (int i = 0; i < N; i++) {
         C.add(Integer.parseInt(br.readLine()));
      }

      C.sort(Collections.reverseOrder());

      int answer = 0;
      
      for (int i = 0; i < N; i++) {
         if ((i + 1) % 3 == 0) {
            continue;
         }
         answer += C.get(i);
      }

      System.out.println(answer);
   }
}