As a first step, provide an example that compiles. Your example has too many opening and too few closing curly braces.

foreach ($input)

There's no need for a foreach loop over one element, so leave that out.

I rewrote your example in a way that I think you intended: 

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";
    }
}

[download]

And this is how a run could look like: 

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

[download]

In reply to Re: Search a hash for STDIN and report findings by moritz
in thread Search a hash for STDIN and report findings by trenchwar

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