+ 2

You can first take off the last digit with %10, then /= 10 the number, until only a digit left.
That way, you can get the edge tickets.
(Can you infer from this explanation how to do the final step?)

+ 1

What do you have to do in order to make two digits become an actual multidigit number?
How can 1 and 2 become 12?
Look at the procedure I described. It is related to that.