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A train has to reserve all blocks till he reaches a "save" place. It is not allowed to leave, if one of this blocks is already reserved. Only he should be allowed to change switches and power on the reserved blocks.
Before entering a new block a train should set the corresponding signals and switches. You have to change the The speed a block should be set before entering it. At this time it should have the same speed as the block the train is leaving.
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