problem 4 clarification#2

Q. Prob. 4 states that c will always be written with the min. digits. The example given as f=4137, c=223 gives r=4223. But if given 4137-4223 as input, the min. digits for c is 23. Are there test cases like this?

A. It is true that 4137-223 is not the smallest possible representation of the range 4137-4223, but, given 4137-223, the correct decompression is 4137-4223.

A program that generated 4137-223 would be judged incorrect because 4137-23 is the shortest compressed representation of this range.