#include <iostream>

int main()
{
    long N;
    int a,b,c;
    int num = 0;
    std::cin >> N;
    std::cin >> a >> b >> c;
    num=(N / a) + ((N / b) - (N / b / a)) + ((N / c) - (N / a / c) - (N / b / c));
    std::cout << num << std::endl;
    
    return 0;
}