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XOR Challenge

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: less thancomments@mathschallenge.netgreater than
To: less thanmastermind@coolmail.co.ukgreater than
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
less thanspcgreater than
 
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?

Problem ID: 1 (Aug 2000)     Difficulty: 3 Star

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