Island Networks
by Kevin J. Lin
You've been hired by a certain television network to setup the Internet connection for their new gameshow. Informed that the network cabling has already been laid, you head to the site expecting an easy job. Unfortunately, it seems this new gameshow involves stranding a bunch of people on a desert island. Funnier than Gilligan's Island, but in a less cerebral kind of way. Anyway, the first problem is that the network cable runs underwater from the desert 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 by the airline. The only equipment you have with you is a sharpie marker, a lightbulb and a battery. While the network was thoughtful enough to provide a canoe, you really want to minimize trips to island. You're not lazy, it's just that you've met the contestants. In how few trips can you determine which wires at the network's end correspond to which wires on the deserted island's end?
Assume:
- 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 at either end is willing or able to assist you, you're on your own.
- You may use the marker to label the wire ends however you like.