You have a simple (base-ten, whole number) calculator which can perform only two operations: visually reversing a number, and adding seven.
Prove that you can use this calcluator to convert any number to 1.
Notation: use ~ to denote reversal, as in
~53 = 35
(In reply to remarks: Not the most rigorous proof, but....
by Ady TZIDON)
ady wrote: "RE: ' Reverse the digits of N.' N was defined as an 1-digit number."
Initially it was a 1-digit number, and then it keeps getting incremented by 7 at that LOOP.
Posted by Penny
on 2004-02-23 02:11:20