#include<cstdio>
#include<vector>
#include<algorithm>


using namespace std;


int min_u(int& m, int v)
{
	if(m>v)
	{
		m=v;
		return 1;
	}
	return 0;
}


int solve(vector<int>& v, vector<int>& dp, int s, int rest)
{
	vector<int> w;
	int i, j, k, ret=10000;

	if(rest<=0)
	{
		return dp[v[0]]+dp[v[1]]+dp[v[2]]+dp[v[3]];
	}

	for(i=s;i<=v[3];i++)
	{
		w=dp;
		for(j=0;j+i<=30;j++)
		{
			for(k=0;j+i*k<=30;k++)
			{
				min_u(w[j+i*k], dp[j]+k);
			}
		}
		min_u(ret, solve(v, w, i+1, rest-1));
	}
	return ret;
}


int main(void)
{
	vector<int> dp(30+1);
	vector<int> v(4);
	int p, k;

	fill(dp.begin(), dp.end(), 100000);
	dp[0]=0;

	while(scanf("%d%d%d%d", &v[0], &v[1], &v[2], &v[3])==4)
	{
		sort(v.begin(), v.end());
		p=-1;
		k=0;
		for(int x: v)
		{
			if(p!=x) k++;
			p=x;
		}
		if(k<=3)
		{
			printf("4\n");
			continue;
		}
		printf("%d\n", solve(v, dp, 1, 3));
	}

	return 0;
}