【192】Word Frequency   

Write a bash script to calculate the frequency of each word in a text file words.txt.

For simplicity sake, you may assume:

• words.txt contains only lowercase characters and space ' ' characters.
• Each word must consist of lowercase characters only.
• Words are separated by one or more whitespace characters.

Example:Assume that words.txt has the following content:the day is sunny the thethe sunny is isYour script should output the following, sorted by descending frequency:the 4is 3sunny 2day 1Note:Don't worry about handling ties, it is guaranteed that each word's frequency count is unique.Could you write it in one-line using Unix pipes?

【193】Valid Phone Numbers    

【194】Transpose File   

【195】Tenth Line