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exercism fetch racket grains

Grains

Calculate the number of grains of wheat on a chessboard given that the number on each square doubles.

There once was a wise servant who saved the life of a prince. The king promised to pay whatever the servant could dream up. Knowing that the king loved chess, the servant told the king he would like to have grains of wheat. One grain on the first square of a chess board. Two grains on the next. Four on the third, and so on.

There are 64 squares on a chessboard.

Write code that shows:

For bonus points

Did you get the tests passing and the code clean? If you want to, these are some additional things you could try:

Then please share your thoughts in a comment on the submission. Did this experiment make the code better? Worse? Did you learn anything from it?


For installation and learning resources, refer to the exercism Racket page.

You can run the provided tests through DrRacket, or via the command line.

To run the test through DrRacket, simply open the test file and click the 'Run' button in the upper right.

To run the test from the command line, simply run the test from the exercise directory. For example, if the test suite is called hello-world-test.rkt, you can run the following command:

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raco test hello-world-test.rkt

which will display the following:

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raco test: (submod "hello-world-test.rkt" test)
2 success(es) 0 failure(s) 0 error(s) 2 test(s) run
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2 tests passed

Source

JavaRanch Cattle Drive, exercise 6 http://www.javaranch.com/grains.jsp

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.