Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...

This is a puzzle question ....

The warden meets with 23 new prisoners when they arrive. He
tells them, "You may meet today and plan a strategy. But
after today, you will be in isolated cells and will have no
communication with one another.

"In the prison is a switch room, which contains two light
switches labeled A and B, each of which can be in either the
'on' or the 'off' position. I am not telling you their
present positions. The switches are not connected to anything.

"After today, from time to time whenever I feel so inclined,
I will select one prisoner at random and escort him to the
switch room. This prisoner will select one of the two
switches and reverse its position. He must move one, but
only one of the switches. He can't move both but he can't
move none either. Then he'll be led back to his cell.

"No one else will enter the switch room until I lead the
next prisoner there, and he'll be instructed to do the same
thing. I'm going to choose prisoners at random. I may choose
the same guy three times in a row, or I may jump around and
come back.

"But, given enough time, everyone will eventually visit the
switch room as many times as everyone else. At any time
anyone of you may declare to me, 'We have all visited the
switch room.' and be 100% sure.

"If it is true, then you will all be set free. If it is
false, and somebody has not yet visited the switch room, you
will be fed to the alligators."

What is the strategy they come up with so that they can be free?

Answer Posted / pawan

THere are two cases : 1) switch 1 is on and 2)switch 1 is
off. And all except leader will on the first switch if it of
only during their first visit. The position of second switch
i not necessary. 1st case : If the leader goes first he will
make the switch off. so the remaining if goes will turn it
on...so 22 will be wrong because leader started with it so
he cannot be sure after turning off 22 times that all have
visited because therse possibility that one of them have not
visited. If leader does not go first then 22 is enough ...to
be same he tells after 23 switches......case 2: it doesnt
matter if leader is sent first or later...after 23 he can
safely say all have visited

Is This Answer Correct ?    0 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Wrtite a JCL for sorting a file with start from 36 postion lenth 9 excluding a num eq to 98768. for 3 marks mainframe

1855


what is the filters in biztakk server? where it can use?

2090


Write a function which accepts a sentence as input parameter.Each word in that sentence is to be reversed. Space should be there between each words.Return the sentence with reversed words to main function and produce the required output. for eg:- i/p: jack jill jung kill o/p: kcaj llij gnuj llik

2336


hi This is radhika.Can anyone help me to know the question papers of NATIONAL INFORMATICS CENTRE for the post of scientific officer/engineer? if anyone know plz tell me question paper pattern

2072


what are the topics choosen for jam round for interviews

1645


How to connect to ms word wit VB ojective is to prepare s/w to generate question paper , selects questions randomly from the ms access , database

2450


Given an array all of whose elements are positive numbers, find the maximum sum of a subsequence with the constraint that no 2 numbers in the sequence should be adjacent in the array. So 3 2 7 10 should return 13 (sum of 3 and 10) or 3 2 5 10 7 should return 15 (sum of 3, 5 and 7)

1165


Q1.Write a C program which asks the user for a number between 1 to 9 and shows the  number. If the user inputs a number out of the specified range, the program should  show an error and prompt the user for a valid input.

2700


3. What is the difference between testing and Quality Assurance?

2003


how much fee for deccan soft institute .how to block seat for sandeep sir class reply soonnnn 

2226


why not instantiating servet using new operator?

1949


Write a program to find factorial of a number using functions

1679


I am looking for selenium RC online Training in chennai. can any one tell me the best institute

1957


what are stubs related to foxpro?

2086


How to use string functions in QTP?give some examples

7877