#include <iostream.h>


int main ()
{
float a,f,x,b,c,h;
float xn,xk;
cout<<"vvedite  xn i xk"<<endl;
cin>>xn>>xk;
cout<<"VVedite  chag"<<endl;
cin>>h;
cout<<"vvedite  x i b"<<endl;
cin>>x>>b;
if(x<3&&b!=0)
{
    cout<<"VVedite a i c"<<endl;
    cin>>a>>c;
 f=a*x*x-b*x+c;
  cout<<"rezultat"<<f<<endl;
}
else
{
if(x>3&&b==0)
{
     cout<<"VVedite a i c"<<endl;
    cin>>a>>c;
    f=x-a/x-c;
     cout<<"rezultat"<<f<<endl;
}
else
{
     cout<<"VVedite   c"<<endl;
    cin>>c;
    if(c!=0)

                       f=x/c;

        else
         cout<<"net  resheniya"<<endl;

}
}

   return 0;
}