LinkedList by User Input

[SantiagoPB]

What will data be when the user enters -1? How can you use that information to break out of the input loop?

The program should work as follows for inputs:

The user:

Type 3 and press enter.
Type 4 and press enter.
Type 7 and press enter.
Type -1 and press enter. The program starts and gives the following output:

3 4 7

The -1 is used to start the program and start creating the LinkedList. The program should not write -1 to the result.

My problem starts in the line #25 because I don't know how to write this part of the program.