i tried fixing it using arrays :)

#!/usr/bin/perl
open FILE,"sampledata";
@arr = <FILE>;
chomp @arr;
close(FILE);
local $,="\n";
while(@arr) {
my @reslt;
@str = shift @arr;
push(@reslt,$str[0]);
while (@str) {
  $flag = 0;
  $str = shift @str;
  $s1,$s2,$flag) = split(/ /,$str);
  my $count = -1;
  my $acount = 0; #to arrange o/p
  foreach(@arr) {
        $count++;
        if($_ =~ /$s1|$s2/) {
              $acount++;
              if($acount == 2 || $flag == 1) {
                  unshift(@reslt,$_);
                  unshift(@str,$_." 1");
              }
              else {
                   push(@reslt,$_);
                   push(@str,$_);
              }
              splice(@arr,$count,1);
         }
    }
 }
 print @reslt,"\n";
}
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