use strict;

my %ID;

#load the data...
while (<DATA>) {
  chomp;
  my @result = split (/\|/);
  my $rec = {LastName=>$result[1], FirstName=>$result[2], 
	     TimeIN=>$result[3], TimeOUT=>$result[4]};
  push @{$ID{$result[0]}}, $rec;
}

#print the data
foreach my $key(sort keys %ID){
  print "$key\n";
  foreach (@{$ID{$key}}){
    print "$_->{LastName}\n";
  }
}

__DATA__
0001|Flintstone|Fred|0900|1300
0001|Flintstone|Fred|0900|1100
0001|Flintstone|Fred|1200|1630
0002|Flintstone|Wilma|0900|1500
0002|Flintstone|Fred|0930|1100
0003|Rubble|Barney|0900|1100