Ampligence Interview Question : Bin

Let's rewind the time back 20 years, when a phone is just a phone: no camera, no online connection, no GPS. A phone can only do basic talking and texting.

A non-Chinese-speaking computer science professor got lost somewhere in China during an academic meeting travel. Despite he is a computer science professor, he didn't bring a computer with him. The only things he has with him are some blank paper from the meeting, a pen, and a phone which is almost about to run out of charge. Worse than that, the professor broke his legs and he can only sit there wait for his friend to help. The professor has only one Chinese friend in China, who is a math professor. As the CS professor about to call for help, he realized that he has no idea where he is at, nor how to describe where he is at. He sees lots of street signs and store signs, but he couldn't understand the Chinese characters. His friend, the math professor, however, is a local Chinese, so he could understand Chinese; as long as he knows what the adjacent street signs/store signs says, he can come to rescue.

First time in China, the biggest problem is that the CS professor understands no Chinese at all. He doesn't even know how to describe a Chinese character in terms of the strokes: "heng", "shu", etc. And it's 3AM, there is nobody else on street that can help. (The street lights are on, so he can see everything alright.)

The phone is very low on battery, it could die at any moment. And his broken legs are bleeding; looks like he couldn't make it to the sunrise. The CS professor urgently needs to EFFICIENTLY communicate lots of Chinese characters to suggest his location, via a plain phone, while he understands no Chinese at all.

What could he do?

Be realistic!

Remember: no camera, no online connection, no GPS.

You will be evaluated based on 1 simplicity of fixed cost, 2 efficiency of variable cost, 3 generality

1 simplicity of fixed cost

• How easy to explain the protocol?
• How short to explain the protocol?

2 efficiency of variable cost

• How short is your message, remember "The phone is very low on battery, it could die at any moment. "
• how easy to encode the message, by the math professor.
• how easy to decode the message. by the CS professor.

3 generality

• how much does your protocol work on other situation?
• on another language?
• on another media?
• on another purpose?
• on another scale of the message size?