Problem 1941. Lowest sum from a group of digits

Hi there. It's James's daughter here again, and my third grade math teacher is up to her old tricks. This time, she's giving us an even number of digits between 0-9, and she wants us to come up with the smallest possible sum of two numbers that are the same length.

For example, if we're given [0 1 2 3], the smallest sum we can get using those numbers by adding two 2-digit numbers together is 33. That's either 10+23 or 13+20. We don't need to know what the two original numbers are, just what their sum is. We also can't start any of our numbers with a zero, because that's cheating.

You guys did a great job with my earlier problems, and even taught my dad a few things about MATLAB! I hope you can help me out with this one as well!