R,G,B = map(int,input().split())

left = 0
right = 10**7 

ans = 0

def search(mid,R,G,B):

     count = 0
     s = min(R,G,B)
     R -= mid
     G -= mid
     B -= mid
     count += max(R//2,0) + max(G//2,0) + max(B//2,0)
     if((s + count) >= mid):
        return True
     else:
        return False   




while abs(left - right) > 1:
    mid = (left + right) // 2
    if(search(mid,R,G,B)):
        left = mid
        ans = max(ans,mid)
    else:
        right = mid   
print(ans)