Locks - this is the main barrier for all kinds of thieves. The richer the person, the more he cares about the safety of the property and here the foremost castles come to the fore. What are the only ways not to invent to block the doors: from usual massive padlocks, to super modern ones with remote control or such, as in the game Laser Locked - laser locks. You will have to test the new invention for strength. Imagine that you are a common thief who must make his way through a complex security system consisting of many locks. Your task is to combine the same color segments between the two elements of the chain.