#include <iostream>
#include <vector>
#include <list>
#include <deque>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <algorithm>
#include <cmath>
#include <cstring>

using namespace std;

#define FOR(x,y) for(int x = 0;x < (y);x++)
#define LLI long long int
#define FORR(x,arr) for(auto& x:arr)
#define ALL(a) (a.begin()),(a.end())

#define _L(x) cout<<(x)<<endl
//#define _L(x) ;

template<int um> class UF {
public:
    vector<int> _parent,_rank;
    UF()
    {
        _parent=_rank=vector<int>(um,0);
        for(int i=0;i<um;i++)
        {
            _parent[i]=i;
        }
    }
    
    int Find(int x)
    {
        if(_parent[x] == x)
        {
            return x;
        }
        _parent[x] = Find(_parent[x]);
        return _parent[x];
    }
    
    int Union(int x,int y)
    {
        int xRoot = Find(x);
        int yRoot = Find(y);
        if(_rank[xRoot]>_rank[yRoot])
        {
            _parent[xRoot] = yRoot;
           return yRoot;
        }
        if(_rank[xRoot]<_rank[yRoot])
        {
            _parent[yRoot] = xRoot;
            return xRoot;
        }
        if(xRoot != yRoot)
        {
            _parent[yRoot] = xRoot;
            _rank[xRoot]++;
            return xRoot;
        }
        return xRoot;
    }
};

int upperValue = 100000000;
int dp[31];
vector<int> V(4);

int calculate(int rest, int a, int b, int c)
{
    if(rest < 0)
    {
        return upperValue;
    }
    if(rest == 0)
    {
        return 0;
    }
    if(dp[rest] > 0)
    {
        return dp[rest];
    }
    int minValue = upperValue;
    minValue = min(minValue, calculate(rest - a, a, b, c) + 1);
    minValue = min(minValue, calculate(rest - b, a, b, c) + 1);
    minValue = min(minValue, calculate(rest - c, a, b, c) + 1);
    dp[rest] = minValue;
    return minValue;
}

int main() {

    FOR(i, 4)
    {
        cin >> V[i];
    }
    sort(V.begin(), V.end());

    int minCost = upperValue;
    for(int a = 1; a <= 28;a++)
    {
        for(int b = a + 1;b <= 29;b++)
        {
            for(int c = b + 1;c <= 30;c++)
            {
                FOR(i, 31)
                {
                    dp[i] = -1;
                }
                int sum = 0;
                for(int i = 3;i >= 0;i--)
                {
                    int r = calculate(V[i], a, b, c);
                    sum += r;
                }
                minCost = min(minCost, sum);
            }
        }
    }
    cout << minCost << endl;
    return 0;
}