Here’s one way to do it:
# program 1: dbmopen(%WORDS,"words",0644); while (<>) { foreach $word (split(/\W+/)) { $WORDS{$word}++; } } dbmclose(%WORDS);
The first program (the writer) opens a DBM in the current directory called
words
, creating files named words.dir and words.pag. Thewhile
loop grabs each line using the diamond operator. This line is split apart using thesplit
operator, with a delimiter of/\W+/
, meaning nonword characters. Each word is then counted into the DBM array, using theforeach
statement to step through the words.# program 2: dbmopen(%WORDS,"words",undef); foreach $word (sort { $WORDS{$b} <=> $WORDS{$a} } keys %WORDS) { print "$word $WORDS{$word}\n"; } dbmclose(%WORDS);
The second program opens a DBM in the current directory called words. That complicated looking
foreach
line does most of the dirty work. The value of$word
each time through the loop will be the next element of a list. The list is the sorted keys from%WORDS
, sorted by their values (the count) in descending order. For each word in the list, we print the word and the number of times the word has occurred.
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