Hi guys, i m having a problem in the following source code. Please see if you can help.Thanks a lot.

#include<iostream>
#include<iomanip>
#include<cctype>
using namespace std;
int main()
{
    char response='y';
    int num,sum=0;
    do{
        cout<<"Enter a number: ";
        cin>>num;
        sum+=num;
        cout<<"Do you want to enter another number?(y/n) ";
        cin>>response;
        response=tolower(response);
        while((response!='y')||(response!='n'))
        {
            cout<<endl<<"Please enter y to continue or n to end. ";
            cin>>response;
        }
    }while(tolower(response=='y'));

    cout<<endl<<"The sum of numbers that you entered is "<<sum<<"."<<endl;

    return 0;
}

When executed, the program enters an infinite loop (i m clueless about that!!).
This was compiled on VC++ 6.0. Make appropriate changes for your compiler.
Pleeeeeeeeeeeeeeeeeeeeeeez help!

Try this:

while((response!='y')&&(response!='n'))

i beleive that the problem is in the outer while loop, the condition
while(tolower(response=='y')) will always remain true.
coz response=='y' is a logical statement that would return 0 or 1 to the tolower function and that would always remain true may be it will work if you make it

while(tolower(response)=='y');

Your statement
"while((response!='y')||(response!='n'))"
says while response is not equal to 'y' OR response is not equal to 'n' - this will cause an infinite loop since the condition will always be true!

Change the OR (||) tp AND (&&)

After the second "cin >> response;" put "response = tolower(response); then the second while statement becomes "while (response == 'y');"

Alan

simply write while(response == 'y') in the outer while loop, it should work..