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.
For example, assume that words.txt has the following content:
the day is sunny the the
the sunny is is
Your script should output the following, sorted by descending frequency: 
the 4
is 3
sunny 2
day 1 
 
 
 
 
 
Solution: 
----------------------- 
 
cat word.txt | tr -s ' ' '\n' | sort | uniq -c | sort -r | awk '{print $2, $1}'


note:  tr -s means: --squeeze-repeats   replace each input sequence of a repeated character that is listed in SET1 with a single occurrence of that character






































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