def solve(v0, v1, v2, v3):
    V = [v0, v1, v2, v3]
    if len(set(V)) < 4:
        return 4
    V.sort()
    min_n = sum(V)
    v3 = V[-1]
    for a in range(1, v3 - 1):
        for b in range(a + 1, v3):
            for c in range(b + 1, v3 + 1):
                n = count(a, b, c, V)
                if n < min_n:
                    min_n = n
    return min_n

def count(a, b, c, V):
    v3 = V[-1]
    dp = [float('inf')] * c + [0] + [float('inf')] * v3
    for i in range(c + 1, c + v3 + 1):
        dp[i] = 1 + min(dp[i - a], dp[i - b], dp[i - c])
    return sum(dp[c + vi] for vi in V)

v0, v1, v2, v3 = map(int, input().split())
print(solve(v0, v1, v2, v3))