Laying a Cable…
You are an internet technician. You have a job to do where the cabling has already been laid, so you head to the site expecting an easy job. Unfortunately, it seems this network cable runs underwater from one island to another nearby island. The second problem is that the cable consists of ten individually shielded wires, all unmarked.
Your networking kit was lost on the journey to the first island (eaten by sharks). The only equipment you have with you is an indelible marker, a lightbulb and a battery. While the company was thoughtful enough to provide a canoe, you really want to minimize trips between the islands. You’re not lazy, it’s just that you’ve met the local sealife.
In how few trips can you determine which wires at the network’s end correspond to which wires on the deserted island’s end? And of course, explain your answer!
Assume that not only are you incredibly dedicated to risk shark infested waters, but also:
• The individual wires are stripped bare, and may be connected to each other, and or the battery or light bulb.
• The light bulb will light if it completes a circuit with the battery.
• The cabling has negligible resistance.
• No-one is available, willing or able to assist you, you’re on your own.
• You may use the marker to label the wire ends however you like.