v=list(map(int, input().split()))
m=max(v)
INF=1000
ans=INF
for a in range(1, m+1):
    for b in range(1, a+1):
        for c in range(1, b+1):
            dp=[INF]*(m+1)
            dp[0]=0
            for i in range(1, m+1):
                if i>=a:
                    dp[i]=min(dp[i], dp[i-a]+1)
                if i>=b:
                    dp[i]=min(dp[i], dp[i-b]+1)
                if i>=c:
                    dp[i]=min(dp[i], dp[i-c]+1)
            ans=min(ans, dp[v[0]]+dp[v[1]]+dp[v[2]]+dp[v[3]])
print(ans)