R,G,B = map(int,input().split())
high = 10**7+1
low = 0
while high-low>1:
    mid = (high+low)//2
    x,y,z = R,G,B
    cmin = min(x,y,z)
    cnt = cmin
    x -= cmin
    y -= cmin
    z -= cmin
    x,y,z = sorted([x,y,z])
    while z>=3:
        if y==0:
            k = z//5
            cnt += k
            z -= 5*k
            break
        z -= 2
        x += 1
        cnt += 1
        x -= 1
        y -= 1
        z -= 1
        x,y,z = sorted([x,y,z])
    if cnt>=mid:
        low = mid
    else:
        high = mid
print(low)