Introduction - If you have any usage issues, please Google them yourself
1, Topic: data files known source.txt in 20 there are four integer, read the document, these few, and then statistics of the various spaces on each four-digit number is 0 or 2 or 4 or 6 or 8 the number of a few, and these four-digit number and the smallest four-digit sequence deposited by dest.txt file.