Title: Microsoft Interview Problem
 
 Solve it in 10 min!!!
 
 An actual subject: MS Interview problem
 This question is asked at Microsoft job interviews.  The interviewer said 
 it should take you 10 min max. 
 There are 4 men who want to cross a bridge.  They all begin on the same 
 side.  You have 17 minutes to get all of them across to the other side.  It 
 is night.  There is one flashlight.  A maximum of two people can cross at 
 one time.  Any party who crosses, either 1 or 2 people, must have the 
 flashlight with them. The flashlight must be walked back and forth, it 
 cannot be thrown etc. Each man walks at a different speed.  A pair must 
 walk together at a rate of the slower man's pace.
 Man 1: 1 minute to cross.
 Man 2: 2 minutes to cross.
 Man 3: 5 minutes to cross.
 Man 4: 10 minutes to cross.
 For example, if Man 1 and Man 4 walk across first, 10 minutes have elapsed 
 when they get to the other side of the bridge.  If Man 4 returns with the 
 flashlight, a total of 20 minutes have passed, and you have failed the 
 mission.
 See how quickly you can solve this! 
 p.s. The flashlight cannot shine a long distance.  No one can be carried, 
 etc.  (This is a straightforward problem.  There are no tricks.
 
  
 
 
 From: Hank
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 The numbers represent the men with their respective required crossing
 time.  SideX represents where the men are after each "move".
 
 Side1 		Bridge			Side2			Time Elapsed
 1,2,5,10
 5,10			1,2->				1,2			2
 2,5,10		<-2				1				+2 = 4
 2				5,10->			1,5,10		+10 = 14
 1,2			<-1				5,10			+1 = 15
 				1,2->				1,2,5,10		+2 = 17
 
 	
  

Wil Stark, wstark04 (at) pobox _dot_com

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