Add: Word Frequency

Author: openset

Diff for: problems/word-frequency/README.md

@@ -5,6 +5,10 @@
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 ## 192. Word Frequency (Medium)
 
 <p>Write a bash script to calculate the frequency of each word in a text file <code>words.txt</code>.</p>

Diff for: problems/word-frequency/word_frequency.bash

@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+
+# Read from the file words.txt and output the word frequency list to stdout.
+
+awk '{for(i=1;i<=NF;i++) a[$i]++} END {for(k in a) print k,a[k]}' words.txt | sort -k2 -nr

Diff for: problems/word-frequency/words.txt

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+the day is sunny the the
+the sunny is is