I've made a simple console game just for fun, but I cant get random() or mult() to work.

Heres the code how it would work:

Code:
#include <iostream.h>
#include <fstream.h>
#include <iostream>
#include <fstream>
int main()
{
  int input;
  cout<<"--Main Menu--"<<endl;
  cout<<"1. Play Game"<<endl;
  cout<<"2. Exit"<<endl;
  cout<<"Please enter your option: ";
  cin>>input;
  switch (input)
  {
    case 1:
      int input2;
      int x;
      int y;
      int z;
      x=1;
      y=2;
      z=2;
      cout<<"What is "<<x<<"x"<<y<<endl;
      cin>>input2;
      switch (input2)
      {
      case 2:
        cout<<"Congratulations you have won!"<<endl;
        return 0;
      default:
        cout<<"Sorry, you have lost"<<endl;
        return 0;
      }
    case 2:
      return 0;
    default:
      cout<<"Error! Exiting Game!"<<endl;
      return 0;
  }
  return 0;
}
But i want it to look like this:

Code:
#include <iostream.h>
#include <fstream.h>
#include <iostream>
#include <fstream>
int main()
{
  int input;
  cout<<"--Main Menu--"<<endl;
  cout<<"1. Play Game"<<endl;
  cout<<"2. Exit"<<endl;
  cout<<"Please enter your option: ";
  cin>>input;
  switch (input)
  {
    case 1:
      int input2;
      int x;
      int y;
      int z;
      x=random(10);
      y=random(10);
      z=mult(int x, int y);
      cout<<"What is "<<x<<"x"<<y<<endl;
      cin>>input2;
      switch (input2)
      {
      case z:
        cout<<"Congratulations you have won!"<<endl;
        return 0;
      default:
        cout<<"Sorry, you have lost"<<endl;
        return 0;
      }
    case 2:
      return 0;
    default:
      cout<<"Error! Exiting Game!"<<endl;
      return 0;
  }
  return 0;
}
Note that int x and y are random, and z is the product of x and y.

Can anyone help me? Im a beginner by the way