Trying to create an if/else statement for a string

[magnifik]

Homework Statement

I need to make an error message that says "You must enter y or n" for a program. Right now I have this... this is only the part that i need help with, not the whole code.

cout << "Student? (y/n): ";
string student;
getline(cin, student);


i need to now make an if else statement like

if (_________){
cout << "You must enter y or n" << endl;
return 1;
}

i'm not sure what to put in the blank. i could do student.empty(), but the error message would only show up if a user didn't input anything. i need to put something in the if function that would cause the error message to show if the user didn't put anything, wrote a capital Y or capital N, wrote some other letter, etc.

 

[py1sl]

hi,
try
if ((not equal to y) or (not equal to x) or (not equal to Y) or (not equal to X))

which will return true if the answer is not any of x, y, X, Y

hope this helps

 

[Mark44]

Homework Statement

I need to make an error message that says "You must enter y or n" for a program. Right now I have this... this is only the part that i need help with, not the whole code.

cout << "Student? (y/n): ";
string student;
getline(cin, student);

I would use a char variable, not named student. A name like student is misleading, since a casual reader of the code would think it represented some attribute of a student, rather than a single character.

I would use getchar() to get the character

i need to now make an if else statement like

if (_________){
cout << "You must enter y or n" << endl;
return 1;
}

Something like this:

if (ch != 'Y' && ch != 'y' && ch != 'N' && ch != 'n')
{
    cout << "You must enter y or n" << endl;
    return 1;
}

i'm not sure what to put in the blank. i could do student.empty(), but the error message would only show up if a user didn't input anything. i need to put something in the if function that would cause the error message to show if the user didn't put anything, wrote a capital Y or capital N, wrote some other letter, etc.

You shouldn't force the user to enter only lower case letters. Any of 'y', 'n', 'Y', or 'N' should be acceptable.

 

[Melawrghk]

I agree with Mark44,

You can have the 4 conditions in your if statement or you can convert the character the user enters to upper case (or to lower case). But that isn't necessary, it just makes the runtime shorter.

 

[DeeNos]

One option could be to use a logical operator to check if the user input is not equal to "y" or "n". For example:

if (student != "y" && student != "n") {
cout << "You must enter y or n" << endl;
return 1;
}

This way, the error message will show up if the user inputs anything other than "y" or "n", including capital letters or other letters.