The purpose of the question is to test task communication and synchronization
of deletion.

The game simulates the old telephone game where a message is passed
around a circle of players. At the end of the game, the original message 
is compared to the final result to see how much it has changed. 

In our case, we just print the message as it travels the circle until 
the game is done. Since we don't have random error introduced by human
players, we simulate random error by perturbing one character of the message 
by a random amount (though we ensure that it stays within the printable
range of ASCII code values).

The game is run with N=5 players, and ends when the message has been
passed around the ring M=2 times. The original message will be "abcdefghijkl\0".
The program only runs one game; in order to see the results of another game,
the program "telephone" must be run again.