for(keys %Hash1) {
  print "$_\n" if exists $Hash2{$_};
}
[download]

though you might be better off to read in the key file, and then go line by line through the main file looking up the lines in the key hash... save lots of memory, probably...

then again... hashes may not be the way to go at all... what does your data look like?

Update hrm... does look a bit like homework... but isn't it summer?

                - Ant
                - Some of my best work - (1 2 3)

but isn't it summer?

Australia? Or any of the other countries "down south"...
--
Mike

You mean... they have SCHOOLS in AUSTRALIA?!?! But that blows my whole theory on the Crocodile Hunter! ;) (is he even really australian?)

                - Ant
                - Some of my best work - (1 2 3)

#!/local/bin/perl -w
 

$build = '';

print "Which build (enter full path name)? \n" ;

chomp($build = <STDIN>);

open(FILE, "/home/me/stuff/input.txt") 
        || die "Could not open input file\n";
open(BUILD_FILE, $build) || die "Could not open input file\n";
 
%file_list = ();
%build_file = ();
while(<FILE>){
        $file_list{$_} = 1;
}
 
while(<BUILD_FILE>){
        $build_file{$_} = 1;
}
 
 
 
foreach $bkey (sort keys %build_file) {
 
    foreach $line(keys %file_list){
            if ($line =~ $bkey){
               print "YES\n";
            }
            else{
            print "NO\n";
            }
    }
}
 
close(FILE);
close(BUILD_FILE);
[download]

You're missing the point of hashes, I'm afraid...

foreach $bkey (sort keys %build_file) {
 
    if (exists $file_list{$bkey})
       print "YES\n";
    }
    else{
       print "NO\n";
    }
}
[download]

The whole idea is that a hash lets you "instantly" look up whether a given key exists in it WITHOUT having to loop over all the keys...

Your code would work, but it would take n*m time, where n's the number of entries in build file, and m's the number in file_list.

This version takes about n time, m times quicker.
--
Mike

Are you looking to get a bunch of "NO" responses? If so, you should just use arrays instead of hashes. As the code is currently written, you never use the "hash-iness" of %file_list and %build_file, and you might as well replace them both with arrays.

If you are looking to only print out lines that are in both files, then you should read one file into a hash and the other into an array, then code something like this:

foreach (@myArray) {
     print "$_\n" if ($myHash{$_});
}
[download]

Hope this helps.

-Ton
-----
Be bloody, bold, and resolute; laugh to scorn
The power of man...

I must say, I don't get it...why use hashes when you only use the keys?
This one works, though I've taken the liberty of using arrays instead, adding use strict, declararations and so on. I tried it with two files, each containing three identical lines, and I got:


Which build (enter full path name)?
/tmp/database.txt
NO
NO
YES
YES
NO
NO
NO
YES
NO
[download]

-----------------

#!/local/bin/perl -w

use strict;
 
my $build = '';

print "Which build (enter full path name)? \n" ;

chomp($build = <STDIN>);

my @build_file = ();
my @file_list = ();

open(FILE, "</home/me/stuff/input.txt") 
        || die "Could not open input file\n";
while(my $Line = <FILE>){
        push (@file_list, $Line);
}
close FILE;

open(BUILD_FILE, '<' . $build) || die "Could not open input file\n";
while(my $Line = <BUILD_FILE>){
        push (@build_file, $Line);
}
close BUILD_FILE;
  
foreach my $bkey (sort @build_file) {
    foreach my $line(@file_list){
            if (index($line, $bkey) >= 0){
               print "YES\n";
            }
            else{
            print "NO\n";
            }
    }
}
[download]



#!s #!s, oh baby when she moves, she moves...

In the meantime you can consider that by saying "compare the elements in Hash1 with the elements in Hash2, and print the element if it matches", you've phrased the question so well that's probably just a question of running "perldoc perldata", then reading and applying the results.

If you'd like to post non-working code to show you've tried, you may have better luck.