Data-type restriction?!

Do you want to mention what programming language you''re using?

Oh!
sorry, since MOST people here use C/C++, I forgot to post that..

anyway, I use C++.

Well, first you will have to get the string that the user inputs from stdin. Let''s say you stored this in a char * array:

char input[64];

Now, to check if the user actually entered something:

if ( input[0] == ''\n'' || strlen( input ) == 0 )
{
// Blank string
}

To check for letters:

index = 0;
while ( index < 64 )
{
if ( !( input[index] >= ''0'' && input[index] <= ''9'' ) && input[index] != ''\n'' )
{
// Something besides number and return entered
}
index++;
}

And then, finally:

int number;
sscanf( input, "%d", number );

Damn!

it''s simple, and also a little long.. "guess I''ll leave that for the GUI version!

but that really helped me understand how to do it, THANKS MAN!!

If you ask for an integer, and the user fails to enter an integer, then cin will set it''s failure. You simply loop until cin doesn''t fail:

int myInt = 0;

cin >> myInt;

while(cin.fail())
{
   cout << "You bastard, enter an integer! ";
   cin.clear();
   cin >> myInt;
}

Heh!
that''s much simpler for me!

I''ll use that now and recompile!

Thanks for the help

sheesh!!

that keeps on displaying "Please enter an integer!" forever!

Here''s how I put your code in mine:

/********************************
* Name: Multiplication Test     *
* Author: Amer Al-Sadiq         *
* Email: nectron101@hotmail.com *
* Date:  April-26th-2004        *
********************************/

#include <iostream>   //for cout and cin.
#include <cstdlib>    //for system commands.
#include <fstream>
using namespace std;

int main()
{
 int main_number, ans;
 int counter = 0;
 char name[20];
 cout << "\t\t\t Multiplication Test" << endl;  //header
 cout << "\t\t\t  By: Amer Al-Sadiq." << endl << endl;  //header

 cout << "Please enter your name: ";
 cin.getline (name, 20); //captures the name entered
 cout << "Now, let''s beggin! " << endl << endl;

 cout << "\nChoose a multiplication number:" << endl << endl;
 cout << "(2),(3),(4),(5),(6),(7),(8),(9)" << endl;
 cin  >> main_number;

 for ( int n=2; n<10; n++)
 {
  cout << main_number << "x" << n << "= ";
  cin >> ans;
  while(cin.fail())     //HERE IS THE CODE BLOCK
  {
   cout << "Please enter an integer!";
   cin.clear();
   cin >> ans;
  }
  if (ans==(main_number*n))
  {
    counter++;
    cout << "Correct! " << endl << endl;
  }
  else
  {
   cout << "Wrong! " << endl;
   cout << "The correct answer is: " << (main_number*n) << endl << endl;
  }
 }
 cout << "Operations are done!" << endl;
 cout << "Check your scores sheet!" << endl;

 ofstream file("myscore.txt", ios::app);
 file << "This is your score sheet " << name << ":" << endl;
 file << "Multiplication Number: " << main_number << endl;
 file << "Correct answers: " << counter << endl << endl;
 file.close();
 cout << "Have a nice day " << name << endl;

 system ("pause");
 return 0;
}
 

Oops, I forgot, you might also need to call cin.sync() after you call cin.clear().