def func(n):
    while 1:
        if A[2] >= 3 and A[1] >= 1:
            A[2] -= 2
            A[0] += 1
            A.sort()
            n = makeNeck(n)
        elif A[2] >= 5:
            A[0] -= 4
            A[1] += 1
            A[0] += 1
            A.sort()
            n = makeNeck(n)
        else:
            break
    return n

def makeNeck(n):
    A[0] -= 1
    A[1] -= 1
    A[2] -= 1
    return n+1


A = list(map(int,input().split()))
A.sort()
ans = min(A)
if ans > 0:
    A[0] -= ans
    A[1] -= ans
    A[2] -= ans
else:
    print(0)
    exit()
ans = makeNeck(ans)
print(func(ans)-1)