#include<iostream>
#include<sstream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<string>
#include<vector>
#include<cmath>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<numeric>
#include<functional>
#include<complex>

using namespace std;
#define BET(a,b,c) ((a)<=(b)&&(b)<(c))
#define FOR(i,n) for(int i=0,i##_end=(int(n));i<i##_end;i++)
#define SZ(x) (int)(x.size())
#define ALL(x) (x).begin(),(x).end()
#define MP make_pair
#define FOR_EACH(it,v) for(__typeof(v.begin()) it=v.begin(),it_end=v.end() ; it != it_end ; it++)
typedef vector<int> VI;
typedef vector<VI> VVI;

int main()
{
    VI V(4);
    FOR(i,4) cin>>V[i];
    int maxV = *max_element(ALL(V));
    int ans = 1<<28;
    for(int A=1;A<=maxV;A++){
        for(int B=A;B<=maxV;B++){
            for(int C=B;C<=maxV;C++){
                VI dp(maxV+1);
                for(int i=1;i<=maxV;i++){
                    dp[i] = 1<<28;
                    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);
                }
                int sub = 0 ;
                FOR(i,4) sub += dp[V[i]];
                ans = min(ans, sub);
            }
        }
    }
    cout<<ans<<endl;
    return 0;
}