use strict;
my %names;

while (<>)
{
  my ($label, $name1, $name2, $name3, $name4) = split /:/;
  $names{$label}{"first"} = {$name1}
  $names{$label}{"second"} = $name2;
  $names{$label}{"third"} = {$name3} 
  $names{$label}{"fourth"} = $name4;
}