This is one of the OLD POTM problems
Long version of the problem.
Back to the list of problems.
Short Problem Description
january, 1993
THE POTM (Programmer/Puzzle/Problem Of The Month)
The POTM presents a programming problem to the community at large and
provides a set of criteria on which the entry will be judged. A deadline
is set and a winner is deduced from the entries sent. An award is made
and the winner becomes famous.
The competition is open to anyone who finds out about the contest.
(have some fun for a change .....)
(For those of you who are new to POTM, we have found it necessary to be very
explicit in the rules - people like to find loopholes and exploit them.
Thus, the description below is inordinately long - at least read the first
section to figure out if you think this would be fun!)
======================== POTM 93-1 ==================================
TASK: You must provide a program that plays the following game:
When provided with a number (say 257), your program may
subtract one of the digits (either 2, 5, or 7) from that
number and output the total (in this case 255, 252, or 250).
Your objective is to avoid having to output zero (0) when
competing with another similar program. If you output a zero
you will lose the game between the programs.