#include <iostream>
using namespace std;

int main()
{
    double a,b,c,d,s;
    cin>>a>>b>>c>>d;
    printf("%.2f",1/((1/a)+(1/b)));cout<<endl;
    s=1/((1/a)+(1/b)+(1/c)+(1/d));
    printf("%.2f",s);
    return 0;
}