V = list(map(int, input().split()))
M = max(V)
ans = 10 ** 18

for A in range(1, M+1):
    for B in range(1, M+1):
        for C in range(1, M+1):
            dp = [10**18] * (M+1)
            dp[0] = 0
            
            for i in range(1, M+1):
                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)
                
            ans = min(ans, dp[V[0]] + dp[V[1]] + dp[V[2]] + dp[V[3]])

print(ans)