Topic Description:
Given a string that contains only lowercase letters and spaces '' returns the length of the last word.
If the last word does not exist, 0 is returned.
Description: A word is defined by letters, but does not contain any spaces of a string
answer:
The first reaction is to see the title split a string! Therefore, direct use of the Spilled () method, need to be determined for an array of strings after division, if the word is not directly returns 0, otherwise return a string length of the last value in the string array.
