Algorithm

Read the data character by character, multiplying by 256 (left-shift 8 times is quicker) and taking the modulo by 34943 each time. At the end of the string, do this another 2 times then output the difference between 34943 and this number in hexadecimal.

Trick

Don't process data after the #.

Input 'the # is not in first column' is not the end.

Default char is signed, so it can create different results for ascii bigger than 127. Beware.

When multiplying 2 times more at the end, don't multiply by 256*256 since 34942*256*256 will explode a standard int. Multiply by 256, take the modulo and multiply by 256 again and take the modulo again.

If ever a string exactly matches 0 modulo 34943 be sure to output 0 and not 34943.

UVa input is difficult : This is a speed problem. Don't even think about using a bigint in base 256 to solve it.

If you are in trouble with the multi-entry input, read my how to read input.

Additional Input

128.in

Additional Output

128.out

Problem

You work for a company which uses lots of personal computers. Your boss, Dr Penny Pincher, has wanted to link the computers together for some time but has been unwilling to spend any money on the Ethernet boards you have recommended. You, unwittingly, have pointed out that each of the PCs has come from the vendor with an asynchronous serial port at no extra cost. Dr Pincher, of course, recognizes her opportunity and assigns you the task of writing the software necessary to allow communication between PCs.

You've read a bit about communications and know that every transmission is subject to error and that the typical solution to this problem is to append some error checking information to the end of each message. This information allows the receiving program to detect when a transmission error has occurred (in most cases). So, off you go to the library, borrow the biggest book on communications you can find and spend your weekend (unpaid overtime) reading about error checking.

Finally you decide that CRC (cyclic redundancy check) is the best error checking for your situation and write a note to Dr Pincher detailing the proposed error checking mechanism noted below.

CRC Generation

The message to be transmitted is viewed as a long positive binary number. The first byte of the message is treated as the most significant byte of the binary number. The second byte is the next most significant, etc. This binary number will be called ``m'' (for message). Instead of transmitting ``m'' you will transmit a message, ``m2'', consisting of ``m'' followed by a two-byte CRC value.

The CRC value is chosen so that ``m2'' when divided by a certain 16-bit value ``g'' leaves a remainder of 0. This makes it easy for the receiving program to determine whether the message has been corrupted by transmission errors. It simply divides any message received by ``g''. If the remainder of the division is zero, it is assumed that no error has occurred.

You notice that most of the suggested values of ``g'' in the book are odd, but don't see any other similarities, so you select the value 34943 for ``g'' (the generator value).

Input and Output

You are to devise an algorithm for calculating the CRC value corresponding to any message that might be sent. To test this algorithm you will write a program which reads lines (each line being all characters up to, but not including the end of line character) as input, and for each line calculates the CRC value for the message contained in the line, and writes the numeric value of the CRC bytes (in hexadecimal notation) on an output line. Each input line will contain no more than 1024 ASCII characters. The input is terminated by a line that contains a # in column 1. Note that each CRC printed should be in the range 0 to 34942 (decimal).

Sample Input

this is a test

A
#

Sample Output

77 FD 
00 00
0C 86

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