#!/usr/local/bin/perl -w 

# prune out duplicate arrays of shell sort steps from the output of
# the sieve driver Korn shell script.

$prev_ratio = (<>);
$prev_values = (<>);

while ( defined ( $new_ratio = (<>) ) && defined( $new_values = (<>) ) )
{

  if ( $prev_values ne $new_values )
  {
    print "$prev_ratio" ;
    print "$prev_values" ;
    $prev_ratio = $new_ratio;
    $prev_values = $new_values;
  }

}

print "$prev_ratio" ;
print "$prev_values" ;
print "$new_ratio" ;
print "$new_values" ;