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# Grains
Write a program that calculates 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 a program that shows:
- how many grains were on each square, and
- the total number of grains
## 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:
- Optimize for speed.
- Optimize for readability.
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?
## Getting Started
Make sure you have read the [getting started with C++](http://help.exercism.io/getting-started-with-cpp.html)
page on the [exercism help site](http://help.exercism.io/). This covers
the basic information on setting up the development environment expected
by the exercises.
## Passing the Tests
Get the first test compiling, linking and passing by following the [three
rules of test-driven development](http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd).
Create just enough structure by declaring namespaces, functions, classes,
etc., to satisfy any compiler errors and get the test to fail. Then write
just enough code to get the test to pass. Once you've done that,
uncomment the next test by moving the following line past the next test.
```C++
#if defined(EXERCISM_RUN_ALL_TESTS)
```
This may result in compile errors as new constructs may be invoked that
you haven't yet declared or defined. Again, fix the compile errors minimally
to get a failing test, then change the code minimally to pass the test,
refactor your implementation for readability and expressiveness and then
go on to the next test.
Try to use standard C++11 facilities in preference to writing your own
low-level algorithms or facilities by hand. [CppReference](http://en.cppreference.com/)
is a wiki reference to the C++ language and standard library. If you
are new to C++, but have programmed in C, beware of
[C traps and pitfalls](http://www.slideshare.net/LegalizeAdulthood/c-traps-and-pitfalls-for-c-programmers).
## Source
JavaRanch Cattle Drive, exercise 6 [view source](http://www.javaranch.com/grains.jsp)