In my project i am reading the XML file and writing into new file updating few data in it, for which i have used hash to check if record exist, I have written the code and its working well, but i was think if there is any smart solution I mean less code to do same task!!!! here is my code:-

sub dispatch
{
    my $HRR_resource = shift;
    my $HRR_wnt = shift;
    my $HRR_unx = shift;
    my $HRR_Scomponent = shift;
    my $HRR_Wcomponent = shift;
    my $Pkey;
    my $Wkey;
    my $Ukey;
    my $SCkey;
    my $WCkey;
    my $Flag;

    open(FR, "<$source_file")|| die "Unable to open input file: $sourc
+e_file $!";
    open(FW, ">$dest_file")|| die "Unable to open output file: $dest_f
+ile $!";

    while (my $line=<FR>)
    {
    $line =~tr/\r\n//d;
    if ($line)
    {
        $Flag = 1;
        if ($line =~ /PLATFORM_INDEPENDENT/){$Pkey = $line};
        if ($Pkey)
        {
            $Flag = undef;
            $Pkey =~ s/\s*//;
            if($Pkey ne '</PLATFORM_INDEPENDENT>')
            {
               if ($line =~ /Id="(.*?)".*?>(.*?)</)
               {
                   my $key_id = $1;
                   my $key_val = $2;

                   if (exists $$HRR_resource{$key_id})
                   {
                        my $val = $$HRR_resource{$key_id};
                        $val =~ /.*?>(.*?$)/;
                        $val = $1;
                        $line =~ s/>.*?</>$val</;
                        print FW "$line\n";
                        delete($$HRR_resource{$key_id});
                   }
                   else
                   {
                        print FW "$line\n";
                   }
               }
               else
               {
                   print FW "$line\n";
               }
            }
            if ($line =~ /<\/PLATFORM_INDEPENDENT>/)
            {
                foreach my $addline(keys %$HRR_resource)
                {
                   print FW  "<RESOURCE Id=\"$addline\" $$HRR_resource
+{$addline}</RESOURCE>}\n";
                }
                print FW "$line\n";
                $Pkey = undef;
            }
        }
        if ($line =~ /WNT/){$Wkey = $line};
        if ($Wkey)
        {
            $Flag = undef;
            $Wkey =~ s/\s*//;
            if ($Wkey eq '<WNT>' && $Wkey ne '</WNT>')
            {
               if ($line =~ /Id="(.*?)".*?>(.*?)</)
               {
                   my $key_id = $1;
                   my $key_val= $2;
                   if (exists $$HRR_wnt{$key_id})
                   {
                        my $val = $$HRR_wnt{$key_id};
                        $val =~ /.*?>(.*?$)/;
                        $val = $1;
                        $line =~ s/>.*?</>$val</;
                        print FW "$line\n";
                        delete($$HRR_wnt{$key_id});
                   }
                   else
                   {
                        print FW "$line\n";
                   }
               }
               else
               {
                   print FW "$line\n";
               }
            }
            if ($line =~ /<\/WNT>/)
            {
                foreach my $addline(keys %$HRR_wnt)
                {
                   print FW  "<RESOURCE Id=\"$addline\" $$HRR_wnt{$add
+line}</RESOURCE>}\n";
                }
                print FW "$line\n";
                $Wkey = undef;
            }
        }
        if ($line =~ /UNX/){$Ukey = $line};
        if ($Ukey)
        {
            $Flag = undef;
            $Ukey =~ s/\s*//;
            if ($Ukey ne '</UNX>')
            {
               if ($line =~ /Id="(.*?)".*?>(.*?)</)
               {
                   my $key_id = $1;
                   my $key_val= $2;
                   if (exists $$HRR_unx{$key_id})
                   {
                        my $val = $$HRR_unx{$key_id};
                        $val =~ /.*?>(.*?$)/;
                        $val = $1;
                        $line =~ s/>.*?</>$val</;
                        print FW "$line\n";
                        delete($$HRR_unx{$key_id});
                   }
                   else
                   {
                        print FW "$line\n";
                   }
               }
               else
               {
                   print FW "$line\n";
               }
            }
            if ($line =~ /<\/UNX>/)
            {
                foreach my $addline(keys %$HRR_unx)
                {
                   print FW  "<RESOURCE Id=\"$addline\" $$HRR_unx{$add
+line}</RESOURCE>}\n";
                }
                print FW "$line\n";
                $Ukey = undef;
            }
        }
 if ($Flag)
         {
            print FW "$line\n";
         }
      }
   }
}
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