#!/usr/bin/env perl 
use strict;
use warnings;

my %count;

while (my $line = <DATA>) {
    my ($key, $field) = split / +/, $line;
    push @{$count{$key}}, $field;
}

for my $key (sort keys %count) {
    print "$key ---> " . scalar @{$count{$key}} . "\n";
    print $_ for @{$count{$key}};
    print "\n";
}

__DATA__
0011   Sally
1122   Brandon
2233   George
0011   Roy
1122   Simson