Add a pipeline version written in Bourne shell

04-candy-factory/tf-04.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+
+grep -o "[A-Za-z][A-Za-z][A-Za-z]*" $1 \
+    | tr '[:upper:]' '[:lower:]' \
+    | grep -Ev "^($(sed  -e 's/,/|/g' ../stop_words.txt))$" \
+    | sort | uniq -c | sort -rn | head -25 \
+    | sed -e 's/^ *\([0-9]*\) *\([a-z]*\)/\2  -  \1/'