Your code could be more efficient, but examining %seen at the end shows you have the data you want. You just need to display it. keys %hashvariable produces a list of the keys of a hash.

foreach my $name (sort keys %seen) {
  printf "%-6s: %-2d\n", $name, $seen{$name};
}
[download]

Output:

dave  : 2
james : 2
jon   : 5
ken   : 3
mike  : 3
[download]

Or, slightly more 'perlish',

printf "%-6s: %-2d\n",$_, $seen{$_} for (sort keys %seen);
[download]