Thread: Buffer Overflow - Stopping this

Ok below is a program we wrote in CS class. I found that by entering too many numbers, in this case 32 9's(bored) i caused a buffer overflow. Now in the sense of making BO's and DOS attacks and such i know that, but how can i adjust my program to allow that many numbers before the thing overflows? Is it my variable types?

Code:

/*	Steven Billington
	SumNum.cpp
	September 23, 2002
*/

#include <iostream.h>
#include <iomanip.h>

const int MAIN_CONST = 5;

int main ()

{

	int givenvalu,j,sum=0;

	for (j=1; j <=MAIN_CONST; ++j)
		{
			cout <<"Please enter a number and press <enter>: ";

			cin >>givenvalu;

			sum += givenvalu;
		}

	cout <<endl;

	cout <<"The sum of the given numbers is "<<sum<<endl;

	cout <<endl;

	cout <<"Goodbye!"<<endl;

	return 0;

}