Write a method that swaps the first and last elements in an ArrayList of Strings.

For example, if we had an ArrayList<String> list with the values [“hello”, “world”]:

swapFirstLast(list)

Should return an ArrayList with the elements:

["world", "hello"]

If we had an ArrayList<String> list with the values [“hello”]:

swapFirstLast(list)

Should return an array with the elements:

["hello"]

swapFirstLast(new ArrayList<String>())

Should return an empty ArrayList:

[]