#!/usr/bin/perl -w
# interleave.pl - Don Yang (uguu.org)
#
# Take input strings (one per line) and mix them on to the same line.
#
# 12/23/11

use strict;

my @lines = <>;
my $length = 0;
foreach (@lines)
{
   chomp;
   if( $length < length $_ )
   {
      $length = length $_;
   }
}

for(my $i = 0; $i < $length; $i++)
{
   for(my $j = 0; $j <= $#lines; $j++)
   {
      if( $i < length $lines[$j] )
      {
         print substr($lines[$j], $i, 1);
      }
      else
      {
         print " ";
      }
   }
}
print "\n";