ITP - exercises - exercise - 15

Use Ruby's Array method delete_if and String method start_with? to
delete all of the words that begin with an "s" in the following array.

arr = ['snow', 'winter', 'ice', 'slippery', 'salted roads', 'white
trees']

Then recreate the arr and get rid of all of the words that start with
"s" or starts with "w".