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

def solve(r, g, b):
    rgb = [r, g, b]
    rgb.sort()
    r, g, b = rgb
    s = r
    g -= r
    b -= r
    r2 = (b - g) // 2
    if r2 > g:
        s += g
        b -= g * 3
        s += b // 5
        return s
    s += r2
    g -= r2
    b -= r2 * 3
    n = g//4
    s += n
    g -= n
    if g == 3:
        s += 1
    return s
 
print(solve(R, G, B))