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Goto keeps looping through

sepetoner (62)
I am trying to get the user to enter yes(y) or no(n). If they enter neither of those, then I want it to say "guess again", and I used the goto function to do this. The problem is that it keeps looping through as if the user keeps pressing a letter besides y or n.

Would a switch function be better for this?

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#include <iostream>
#include <string>
#include <cstdlib>


using namespace std;

int main()
{
 char yn;

    cout << "Is this correct (press y for yes or n for no): ";
    cin >> yn;

    PickAgain:
    if (yn == 'y')
        cout << "Ok!  I randomly choose... ";
    if (yn == 'n')
        cout << "Do";
    if (yn != 'n' || yn != 'y')
        {
        cout << "That is not an option, dumbass.  Pick again.";
        goto PickAgain;
        }
    return 0;
}
Last edited on
vlad from moscow (6539)
You shall forget that C++ has goto statement!

Use while, do-while or other control statements. For example

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    char yn;

    do
    {
        cout << "Is this correct (press y for yes or n for no): ";
        cin >> yn;

        if (yn == 'y')
            cout << "Ok!  I randomly choose... ";
        else if (yn == 'n')
            cout << "Do";
        else 
            cout << "That is not an option, dumbass.  Pick again.";
    } while ( yn != 'y' && yn != 'n' );


Or instead of if-else you can use switch inside the loop

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    char yn;

    do
    {
        cout << "Is this correct (press y for yes or n for no): ";
        cin >> yn;

        switch ( yn )
        {
            case 'y': case 'Y':
                cout << "Ok!  I randomly choose... ";
                break;
            case 'n': case 'N':
                cout << "Do";
                break;
            default: 
                cout << "That is not an option, dumbass.  Pick again.";
                break;
        }
    } while ( yn != 'y' && yn != 'n' );


Last edited on
LimeOats (43)
While it is bad practice to use goto statements, there are certain situations where they come in handy. Your problem isn't a problem with the goto at all. To fix your program, do this:

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#include <iostream>
#include <string>
#include <cstdlib>


using namespace std;

int main()
{
 char yn;

    cout << "Is this correct (press y for yes or n for no): ";
    
    PickAgain:

    cin >> yn;
    if (yn == 'y')
        cout << "Ok!  I randomly choose... ";
    else if (yn == 'n')
        cout << "Do";
    else if (yn != 'n' && yn != 'y')
        {
        cout << "That is not an option, dumbass.  Pick again.";
        goto PickAgain;
        }
    return 0;
}
Last edited on
TheIdeasMan (6782)
I agree with vlad. Edit: about the goto

Except I hate this logic

( yn != 'y' && yn != 'n' )

I prefer to do use a boolean QuitValue with a switch inside a while loop.

Switch statements are good if you need to extend the logic to include other things, but if it is a yes no answer then use if else

Last edited on
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