a, b, c = map(int, input().split())
ans = 0
d = min(a, b, c)
ans += d
a -= d
b -= d
c -= d


def F(k):
    P = max(k-a, 0)+max(k-b, 0)+max(k-c, 0)
    Q = max(a-k, 0)//2+max(b-k, 0)//2+max(c-k, 0)//2
    return Q >= P


l = 0
r = 10**7+10
while r-l > 1:
    m = (r+l)//2
    if F(m):
        l = m
    else:
        r = m

print(ans+l)