# frozen_string_literal: true

def solve
  N / A + N / B + N / C - N / A.lcm(B) - N / B.lcm(C) - N / C.lcm(A) + N / A.lcm(B).lcm(C)
end

N = gets.to_i
A, B, C = gets.split.map(&:to_i)

puts solve