The following text was written to the standard output stream when the NumberList.java program was executed from IntelliJ.
>>> HELP HELP - display a menu of commands DISPLAY - display the list of numbers PRINT - print a number (FIRST;LAST;nth) SWAP - exchange two elements (nth;mth) ADD - add a number to the list (FIRST;LAST) EXIT - terminate execution of the program >>> display 1 2 3 9 10 11 12 13 14 15 16 17 18 19 20 >>> print first 1 >>> print last 20 >>> swap 1 2 >>> display 2 1 3 9 10 11 12 13 14 15 16 17 18 19 20 >>> add first 2 >>> display 2 2 1 3 9 10 11 12 13 14 15 16 17 18 19 20 >>> add last 3 >>> display 2 2 1 3 9 10 11 12 13 14 15 16 17 18 19 20 3 >>> show numbers ### Unrecognizable command: show >>> ### Unrecognizable command: numbers >>> display 2 2 1 3 9 10 11 12 13 14 15 16 17 18 19 20 3 >>> exit