Trouble with a search hw problem.

[frasifrasi]

This specific homework problem asks us to:

 A String variable, fullName, contains a name in one of two formats:
last name,first name (comma followed by a blank), or
first namelast name (single blank)
 Extract the first name into the String variable firstName and the last name into the String variable lastName. 
Assume the variables have been declared and fullName already initialized. 
You may also declare any other necessary variables.

My answer:

int a = fullName.indexOf(",");
	    int b = fullName.indexOf(" ");
	    
	    if(a >= 0){
        String [] temp = null;
         temp = fullName.split("\\,");

        firstName = temp[1].trim();
        lastName = temp[0].trim();
        
        }
        
        else if(b >= 0){
        String [] temp = null;
         temp = fullName.split(" ");

        firstName = temp[0];
        lastName = temp[1];
        
        }

Which, when I test works, but I get no information why it is not valid from the program/copiler. I am thinking there may be looking for a simpler solution.

Does anyone kno another way of doing this?

[Norm]

I get no information why it is not valid from the program/copiler

What do you get? Is it from the compiler or from exection?

when I test works

I'm confused. Does the program work? or not?
If not, what is wrong with what it does? Could you show the output and explain why it is wrong and what you'd like it to be.

Puttnig comments in code to explain what & why are helpful for anyone to understand what you are trying to do.

[frasifrasi]

It works when tested with print statements but the online hw submission thing does not provide any feedback at all--only, "invalid";

[Norm]

online hw submission

Is hw a program that reads/reacts to your program and produces the response: invalid?

To get any help you'll have to ask the admin person for the hw program. No idea here what that program wants.