Using the numbers on a calculator, and rotating the display 180 degrees, many words can be spelled. In particular, the following numbers can characterize the following letters:
There are a few other options, but we'll stick with these. If the word has a trailing O, the number will need a decimal point to produce a leading zero. Write a function that takes a word (upside down) as input and returns the number entered into the calculator.
This problem is related to Problem 3018.