Largest integer from concatenation
If I have a list of integers, I can concatenate their base-10 strings to get one large integer. However, if I reorder them, then concatenate them, I could get a larger integer. The task here is to find the largest integer you can create by concatenating a given set of integers.
Here are some test cases:
(maxcat [1 2 3 4 5 6 7 8 9]) ;=> 987654321 (maxcat [12 34 56 199]) ;=> 563419912