#include <iostream>
#include <iomanip>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <list>
#include <string>
#define _USE_MATH_DEFINES
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <bitset>
#define REP(i,n) for(int (i)=0;(i)<(n);(i)++)
#define RREP(i,n) for(int (i)=(n)-1;(i)>=0;(i)--)
#define debug(x) cout<<x<<endl
using namespace std;
typedef pair<int,int> P;
typedef priority_queue<int> maxpq;
typedef priority_queue<int,vector<int>,greater<int> > minpq;
typedef priority_queue<P> p_maxpq;
typedef priority_queue<P,vector<P>,greater<P> > p_minpq;
typedef vector<int> veci;
typedef vector<P> vecp;
typedef vector<string> vecs;
typedef long long int LL;
#define INF 2000000000
struct edge{int to,cost;};

int v[4];
int solve(int a,int b,int c) {
	int sum = 0;
	REP(k,4) {
		int dp[31];
		REP(i,31) dp[i] = INF;
		dp[0] = 0;
		for(int i = 1;i <= v[k];i++) {
			if(i-a>=0) dp[i] = min(dp[i],dp[i-a]+1);
			if(i-b>=0) dp[i] = min(dp[i],dp[i-b]+1);
			if(i-c>=0) dp[i] = min(dp[i],dp[i-c]+1);
		}
		if(dp[v[k]]==INF) {
			sum = INF;
			break;
		} else {
			sum += dp[v[k]];
		}
	}
	return sum;
}

int main(void) {
	REP(i,4) cin>>v[i];
	int ans = INF;
	for(int i = 1;i <= 30;i++) {
		for(int j = 1;j <= 30;j++) {
			for(int k = 1;k <= 30;k++) {
				ans = min(ans,solve(i,j,k));
			}
		}
	}
	cout << ans << endl;
	return 0;
}