import fractions

def lcm(x, y):
  return x * y / fractions.gcd(x , y)

n = input()
a,b,c = map(int, raw_input().split())
ans = n/a + n/b + n/c - n/lcm(a, b) - n/lcm(b, c) - n/lcm(a, c) + n/lcm(a,lcm(b,c))
print ans