mathschallenge.net

Problem

Sorting through your emails, and deleting the abundance of junk mail that seems to arrive on a daily basis, your attention is drawn to one particular mail:

----- Original Message -----
From: comments@mathschallenge.net
To: mastermind@coolmail.co.uk
Sent: Saturday, March 1, 2003 1:00 AM
Subject: Only the best need try...

Hi mastermind

So you think you're good at code breaking? I'll tell you how I encoded the message and all you need to do is decode it!

I started by using the table below to change the message into a binary string, then XOR"ed it with the alternating string 101010101..., finally I converted it back into readable text. I guess you'll have to research how XOR works. ;)

Here's the table:

Bin	Chr		Bin	Chr		Bin	Chr		Bin	Chr
00000	spc		01000	H		10000	P		11000	X
00001	A		01001	I		10001	Q		11001	Y
00010	B		01010	J		10010	R		11010	Z
00011	C		01011	K		10011	S		11011	.
00100	D		01100	L		10100	T		11100	,
00101	E		01101	M		10101	U		11101	?
00110	F		01110	N		10110	V		11110	!
00111	G		01111	O		10111	W		11111	-

Here's the encoded message:

,GEXPYFCCOK

Good luck!
mathschallenge.net

Can you decode the message?