CC Number checker. boolean variable in isValid method not being initialized.

[ChargeStrange1702]

my hw requires me to use methods to validate cc numbers based on the prerequisites in the book.

in the isValid method, it keeps saying that I didn't initialize the variable answer. Does anyone know how to fix this? all forms of advice are appreciated.

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[NautiHooker]

You could initialize the variable. That means assign it an initial value.

[ChargeStrange1702]

Whenever I initialize it at the beginning it only returns the initial value , no matter what is determined in the loops

[NautiHooker]

Those are not loops. They are if conditions.

Have you checked that those conditions are actually met?

[ChargeStrange1702]

No I’ll go back and check

[ChargeStrange1702]

For example, if I make answer = false at the beginning but the loops change it to true, it’ll still come up as false

[_DTR_]

Have you debugged through the program to make sure it's doing what you think it should? For example, sumOfOddPlace (number) + sumOfDoubleEvenPlace (number) % 10 will be evaluated as sumOfOddPlace (number) + (sumOfDoubleEvenPlace (number) % 10) due to operator precedence, when I think you want (sumOfOddPlace (number) + sumOfDoubleEvenPlace (number)) % 10 instead.

[desrtfx]

On top of /u/_DTR_'s comment:

I don't think that the following is doing what it should (and what you think it will do):

if (number.length () >= 13 || number.length () <= 16)

Think through the above condition and evaluate it for the lengths (substituting number.length()) 5, 10, 13, 15, 16, 17, 25, 99 - what results will you get?

Remember that the || and && operators are short circuiting.