[-o +-x/ ] [-r range ]
asks you to solve problems in simple arithmetic. Each question must be answered correctly before going on to the next. After every 20 problems, it prints the score so far and the time taken. You can quit at any time by typing the interrupt or end-of-file character.
The options are as follows:
When you get a problem wrong, will remember the numbers involved, and will tend to select those numbers more often than others, in problems of the same sort. Eventually it will forgive and forget.
cannot be persuaded to tell you the right answer. You must work it out for yourself.
``What?'' if you get a question wrong. ``Right!'' if you get it right. ``Please type a number.'' if doesn't understand what you typed.