use strict;
use warnings;

my %passwords = (
        moritz => 'secret',
    );

while(<STDIN>) {
    chomp;
    if (exists $passwords{$_}){
        print "Password from $_ is '$passwords{$_}'\n";
    } else {
        print "No password for $_, sorry\n";
    }
}

##</code><code>##

$ perl script.pl
moritz
Password from moritz is 'secret'
someone else
No password for someone else, sorry