Question

Do While loop on C++

I need to program a do while loop in which the user have to choose between option A,a, B,b or C,c. I need a do while loop that if other letter (different from options is choose) the loop print a cout saying "Invalid selection. Plese, enter the selection again.  

I have one, but isn't working well

int main()

{

char option;

do

{

cout<<"Please choose one of the following options: "<<endl<<endl;

cout<<"Option A - Julian Calendar"<<endl;

cout<<"Option B - Powerlifting"<<endl;

cout<<"Option C - GPA"<<endl<<endl;

cout<<Option :";

cin>>option;

} while (option !='A' || option !='a' || option !='B' || option !='b' || option !='C' || option !='c')

return 0;

}

Answer 1

#include <iostream>

using namespace std;

int main() {
    char option;
    bool is_option_invalid;
    do {
        cout << "Please choose one of the following options: " << endl << endl;
        cout << "Option A - Julian Calendar" << endl;
        cout << "Option B - Powerlifting" << endl;
        cout << "Option C - GPA" << endl << endl;
        cout << "Option :";
        cin >> option;
        is_option_invalid = option != 'A' && option != 'a' && option != 'B' && option != 'b' && option != 'C' && option != 'c';
        if (is_option_invalid) {
            cout << "Invalid selection. Please, enter the selection again." << endl << endl;
        }
    } while (is_option_invalid);
    return 0;
}