$ ./frequency testfile1 testfile2
5 3
2 2
3 2
1 0

##</code><code>##

#!/usr/bin/perl -w
#use strict;
open(FILE2, "<testfile2"); #giving testfile2 data a filehandle
@array2 = <FILE2>; #saving filehandle to array
pop @array2; #getting rid of 0 at end
%hash2 = @hash2{@array2}; #storing contents of testfile2 without 0 to
#a hash
open(FILE1, "<testfile1"); #giving testfile1 data a filehandle 
@array1 = <FILE1>; #saving filehandle to array
pop @array1; #getting rid of 0 at end

foreach $number (keys %hash2) { #go through each of the hashs' keys 
#and assign them to $number for duration of loop some keys might be 
#used more than once
if ($number eq search(@array1)) {#check to see if string $number 
#equals each iteration of subroutine search being passed values of 
#@array1. Would have used another foreach loop here, but parentheses 
#and curly brace placement won't allow it.

$hash2{number} += 1;
}
}
sub search { #subroutine search gets one element of @array1 at a 
#time and returns it. Then moves on to the next value in that array.
foreach (@_) {}
return $_;
}
#Ideally here would like to print the array followed by the hash 
#elements
print (@array, %hash2);

##</code><code>##

foreach $person (sort keys %book) {
if ($books{person}) {
print $person has $books{$person} items\n";
}
}