Logic Puzzle Forums “the robots enigma”
 User Name Remember Me? Password
 FAQ Members List Calendar Search Today's Posts Mark Forums Read

 Thread Tools Display Modes
#1
09-17-2014, 12:42 AM
 koren Junior Member Join Date: Sep 2014 Posts: 2
“the robots enigma”

“THE ROBOTS ENIGMA” puzzle

The basis of this puzzle is Raymond’s Smullyan “Three gods puzzle” but with smaller amount of base data, making it more difficult – more difficult than “The hardest logic puzzle ever…” As you can see, there is an incentive – good luck!

"Three robots A, B, and C are called, in some order, True - (T), False (F) and Random (R). (T) is programmed to speaks truly, (F) – falsely, but whether (R) speaks truly or falsely is a completely random matter.
The robots can answer only YES or NO. Each robot is equipped with two small lamps - red and white. When robot responds – the red light lights up, but you do not know he said YES or NO. When there is no answer – lights up the white light.
Your task is to determine the identities of A, B, and C by asking no more than three questions; each question must be put to exactly one robot".
#2
09-19-2014, 10:18 AM
 Betashadow Junior Member Join Date: Aug 2014 Posts: 1

Omg!! I have been at this for like the past 2 hours. The main catch is that the robots dont answer YES or NO. They simply indicate that they know the answer. Lets hope I get the answer soon...
#3
09-19-2014, 01:48 PM
 koren Junior Member Join Date: Sep 2014 Posts: 2

You're right, good luck.
#4
04-14-2015, 05:52 PM
 lexxns Junior Member Join Date: Apr 2015 Posts: 1
Possible Solution

Hi i'm new to this site hence why iv'e just seen this puzzle, but I think I have a solution. Please correct me if I am wrong.

If you ask robot 1 whether both of the other 2 would answer a question truthfully (T) would answer no since (F) will lie - therefore will show a red light and (R) will also show a red light since it must answer.
(F) would not answer the question since (T) would answer truthfully but (R) may or may not, so this has no true or false answer. - White light.

This same question to robot 2 finds for certain the location of (F), since if there are no white lights yet, robot 3 must be (F)

if (F) is either robot 1 or 2, asking robot 3 whether the other of 1 or 2 would answer a question truthfully gives white if 3 is (T) but red if 3 is (R)

if (F) is robot 3 however asking it whether robot 1 (or 2) would answer a question truthfully gives a red light if robot 1 was (T) or a white light if it was (R) - giving the final solution.

Hopefully I haven't missed anything crucial in all this.
#5
04-15-2015, 08:16 AM
 Chezzik Junior Member Join Date: Dec 2014 Posts: 8

lexxns reply is a little bit hard to follow, but I believe it is completely correct.

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Logic-Puzzles.org Discussion     Questions About Logic-Puzzles.org     Comments, Bugs and Feature Requests Other Logic Puzles     Logic Puzzles and Brain Benders Puzzle Baron's Logic Puzzles - The Book!

All times are GMT. The time now is 11:16 AM.

 Contact Us - Logic Puzzles - Archive - Top