package no027;

import java.util.Arrays;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int[] v = new int[4];
		int[] a = new int[3];
		for(int i=0;i<4;i++) {
			v[i] = sc.nextInt();
		}
		int ans = 1000000;
		for(a[0]=1;a[0]<=30;a[0]++) {
			for(a[1]=a[0]+1;a[1]<=30;a[1]++) {
				for(a[2]=a[1]+1;a[2]<=30;a[2]++) {
					int sum = 0;
					for(int i=0;i<4;i++) {
						int[] dp = new int[v[i]+1];
						Arrays.fill(dp, 10000);
						dp[0] = 0;
						for(int j=0;j<v[i];j++) {
							for(int k=0;k<3;k++) {
								if (j+a[k] <= v[i]) {
									dp[j+a[k]] = Math.min(dp[j+a[k]], dp[j] + 1);
								}
							}
						}
						sum += dp[v[i]];
					}
					ans = Math.min(ans, sum);
				}
			}
		}
		System.out.println(ans);
	}

}