How to organize a given Graph data structure and do analysis?

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algorithm

I'm doing with a rail locomotive positioning system.
The problem or goal is to analyze which rail track a locomotive is running on if multiple parallel rail tracks exisit.
Status of rail switches and the distance from a locomotive to the nearest calibration devices(by using RFID) are known.
The trackes, switches and locomotives are processed in the RAM as a graph.
I really appreciate your helps.