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, with the number 
of grains doubling on each successive square.
There are 64 squares on a chessboard (where square 1 has one grain, square 2 has two grains, and so on).
Write code that shows:
<ul>
<li>how many grains were on a given square, and</li>
<li>the total number of grains on the chessboard</li>
</ul>
<h2>For bonus points</h2>
Did you get the tests passing and the code clean? If you want to, these 
are some additional things you could try:
<ul>
<li>Optimize for speed.</li>
<li>Optimize for readability.</li>
</ul>
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?

Grains

For bonus points