C++ switch Statement check user input value

#include <iostream>
using namespace std;
int main()// ww w.j a  v  a  2 s . c om
{
   int opselect;
   double fnum, snum;
   cout << "Please type in two numbers: ";
   cin  >> fnum >> snum;
   cout << "Enter a select code: ";
   cout << "\n         1 for addition";
   cout << "\n         2 for multiplication";
   cout << "\n         3 for division : ";
   cin  >> opselect;
   switch (opselect)
   {
      case 1:
      cout << "The sum of the numbers entered is " << fnum+snum;
      break;
      case 2:
      cout << "The product of the numbers entered is " << fnum*snum;
      break;
      case 3:
      cout << "The first number divided by the second is " << fnum/snum;
      break;
   }    // end of switch
   cout << endl;
   return 0;
}