Online JudgeProblem SetAuthorsOnline ContestsUser
Web Board
Home Page
F.A.Qs
Statistical Charts
Problems
Submit Problem
Online Status
Prob.ID:
Register
Update your info
Authors ranklist
Current Contest
Past Contests
Scheduled Contests
Award Contest
User ID:
Password:
  Register
Language:
Hide That Number
Time Limit: 1000MSMemory Limit: 65536K
Total Submissions: 5950Accepted: 1733

Description

According to Wikipedia, Cryptography is “the practice and study of hiding information” and this is exactly what Alex is looking for. Ever since he was a kid, Alex was paranoid over someone laying their hands on his phone book. He decided that he must write the numbers in some secret way that only he can decipher. At first he tried quite complex algorithms, but that slowed him down when he needed to dial a number fast. He finally came up with the following algorithm: Rather than writing down the number itself, Alex would shift the number one place to the left (as if multiplying it by 10,) then adding the shifted number to the original. For example, if the phone number was 123, Alex would add 1230 to it, resulting in 1353. To make what he writes looks as a regular phone number, Alex truncates the result (from the left,) so that it has as many digits as the original phone number. In this example, Alex writes 353 instead of 123 in his phone book.

Alex needs a program to print the original phone number given what is written in his phone book. Alex, who by the way is a good friend of Johnny, isn’t that good in arithmetic. It is quite possible that the numbers are messed up. The program should print "IMPOSSIBLE" (without the quotes) if the original number cannot be computed.

Input

Your program will be tested on one or more test cases. Each case is specified on a separate line and is made of a single positive number having less than 1,000,000 digits.

The last line of the input file is made of a single zero.

Output

For each test case, output the result on a single line using the following format:

k. result

Where k is the test case number (starting at 1).

Sample Input

353
9988
123456
0

Sample Output

1. 123
2. IMPOSSIBLE
3. 738496

Source

[Submit]   [Go Back]   [Status]   [Discuss]

Home Page   Go Back  To top


All Rights Reserved 2003-2013 Ying Fuchen,Xu Pengcheng,Xie Di
Any problem, Please Contact Administrator