have you written some code?

Break the problem down into small tasks.

First, you need to find a way to get the first digit and the last digit.

There are many different ways you could get these digits.

One way might be to convert the number into a string. Once you have the string, there are several ways you can get the first and last character.

Convert those characters representing the first and last digit to an int.

Once you have those digits, simply add them together.

/ and % can come handy.