Most likely what is happening is that you are trying to make an Int from a String for something that isn't an int.
That is, your input file would look like this:
Aradon Strider 55555
Mother Strider 44455
Father Strider 21345
Your Enter Data Class reads one line, then another line, then tries to read an int. So
first == "Aradon Strider 55555"
second == "Mother Strider 44455"
zip == Father
When it comes to the "father" and putting it into an Int it doesn't work out.