import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int[] boards = new int[4];
        for (int i = 0; i < 4; i++) {
            boards[i] = sc.nextInt();
        }
        int min = Integer.MAX_VALUE;
        for (int i = 1; i <= 28; i++) {
            for (int j = i + 1; j <= 29; j++) {
                for (int k = j + 1; k <= 30; k++) {
                    int count = 0;
                    int[] values = new int[]{i, j, k};
                    for (int a = 0; a < 4; a++) {
                        int[][] dp = new int[3][boards[a] + 1];
                        count += dfw(2, boards[a], values, dp);
                        
                    }
                   min = Math.min(min, count);
                }
            }
        }
        System.out.println(min);
     }
     
     static int dfw(int idx, int length, int[] values, int[][] dp) {
         if (length == 0) {
             return 0;
         }
         if (idx < 0) {
             return Integer.MAX_VALUE / 10;
         }
         if (dp[idx][length] == 0) {
             dp[idx][length] = Integer.MAX_VALUE / 10;
             for (int i = 0; length >= i * values[idx]; i++) {
                 dp[idx][length] = Math.min(dp[idx][length], dfw(idx - 1, length - i * values[idx], values, dp) + i);
             }
         }
         return dp[idx][length];
     }
}