Counting Down

There is a countdown before rockets liftoff into space--you can see an example in this YouTube video: https://www.youtube.com/watch?v=Vfn_u768UoQ

Write a program 20-CountingDown that:

1. has the user enter a value n that the countdown will begin at
2. uses a while loop and a counter variable i to print the numbers from n down to and including 0
3. prints "Blastoff!" once the loop is done counting down.

Finishing Up

Once your program is working correctly, use your mouse to click-drag over the URL address for your project at the top of the browser window. Copy that link, and give that copied link to the instructor using the procedure given in class.