my %h;

for my $v (qw( a b )) { 
   push @{ $h{key} }, $v;
}

for my $k (keys(%h)) {
   print("$k: ", join(', ', @{ $h{$k} }), "\n");
}
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No, it appears to be much simpler than that. You appear to be having problems with a 1-to-1 mapping.

Keeping the same input format, you have parallel arrays. To associate the elements of each parallel array, you need to iterate over the indexes of the those arrays.

kate
dan
^Z
doug.smith
test
^Z
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print "Enter names of user to add:\n";
chomp( my @users = map lc, <> );

print "Enter names of user to mirror:\n";
chomp( my @exusers = map lc, <> );

my %adds;
fore my $i (0..$#users) {
   $adds{$users[$i]} = qx(ls /home/$exusers[$i]/.bash_profile);
}
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Parallel arrays are rarely a good idea. May I suggest a better input format:

kate doug.smith
dan test
^Z
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my %adds;
print "Enter new user and mirrored user pairs:\n";
while (<>) {
   chomp;
   my ($user, $exuser) = map lc, split;
   $adds{$user} = qx(ls /home/$exuser/.bash_profile);
}
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