Logic Puzzles
Requirement:Algorithm
Railway Engineering. A railway depot has an oval track and two branch lines as shown in the figure below, whis is used to train train drivers, also known as Engin-eers. The specific problem a student Engine-eer is asked to solve is how to move railway carriage A to position B and railway carraiage B to position A without taking any of the railway carriages through the tunel and returning the engine to its starting position. How can it be done?
http://i129.photobucket.com/albums/p239/benchoz/RailwayEngineering.jpg
It was not mentioned it think it is
How can you show the algorithm
I'm not going to go into detail as to how I would do it, but as a clarfication, and maybe even a hint, are you allowed to move the engine through the tunnel??
I might actually confuse you and myself if I tried to explain the answer in writing but I think that allowing the engine to go through the tunnel might unlock some answers of your own.
Well, if it is allowed, here is my solution:
Move the engine forward and then switch the tracks so that the engine can move towards carriage A. Then pull carriage A to the initial position of the engine by switching the tracks. Then move the engine to the initial position of carriage A, again switching the tracks, and this time continue through the tunnel. Then pick up carriage B and move it back to the inital position of carriage A by again switching the tracks. Then go back and pick up carriage A and move it to the initial position of carriage B.
A visual might be easier to understand. I didn't however animate anything so I just used desktop icons with Jing 
http://www.screencast.com/t/snolBqOM
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I'm not going to go into detail as to how I would do it, but as a clarfication, and maybe even a hint, are you allowed to move the engine through the tunnel??
I might actually confuse you and myself if I tried to explain the answer in writing but I think that allowing the engine to go through the tunnel might unlock some answers of your own.
Well, if it is allowed, here is my solution:
Move the engine forward and then switch the tracks so that the engine can move towards carriage A. Then pull carriage A to the initial position of the engine by switching the tracks. Then move the engine to the initial position of carriage A, again switching the tracks, and this time continue through the tunnel. Then pick up carriage B and move it back to the inital position of carriage A by again switching the tracks. Then go back and pick up carriage A and move it to the initial position of carriage B.
A visual might be easier to understand. I didn't however animate anything so I just used desktop icons with Jing
http://www.screencast.com/t/snolBqOM
References :