You can add one or several random numbers into your array variables, but Java does not guarantee that each number is unique. Right-click the Java file you want to edit and select "Open With." ...

Then use the last digit as your random number from 0 to 9,” but the original article says, “Choose a 2-digit number, say 23, your “seed”. Form a new 2-digit number: the 10’s digit plus 6 ...