#!/usr/bin/perl
use warnings;
use strict;

my $filename = "first.txt";
my (@queryx, @queryy, @basex, @basey, %hash, $i, $j, $k, $ss);

open (FILE, $filename) or die "can't open $filename: $!\n"; 

    while(<FILE>)
{
    if ($_ =~ /(\S+)\s+(\S+)/)
 {
    $hash{$1} = $2;
    push(@queryx,$1);
    push (@queryy, $2);
}
    }
    
close(FILE); 
    
my $filename1 = "second.txt";
open (FILE1, $filename1) or die "can't open $filename: $!\n";

        while(<FILE1>)
{
        if ($_ =~ /(\S+)\s+(\S+)/)
 {
        $hash{$1} = $2;
        push(@basex,$1);
        push (@basey, $2);
}
        }

close(FILE1);
$ss = @basex;
print $ss, "\n";
print "Enter the Threshold Value:  \n";
$j= <STDIN>;

open(FILEHANDLE, ">result.cmp") or die "cannot open file for reading: 
+$!";#Creates an output file

$k = 0;

print $k, "\n";

my $a1 = $queryx[0];
my $a2 = $queryx[1];
my $a3 = $queryx[2];

while ($i <= $ss)
{
my $b1 = $basex[$i];
my $b2 = $basex[$i+1];
my $b3 = $basex[$i+2];

my $rr1 = (($a1) - ($b1));
my $rr2 = (($a2) - ($b2));
my $rr3 = (($a3) - ($b3));

my $r1 = sprintf "%.3f", (abs($rr1));
my $r2 = sprintf "%.3f", (abs($rr2));
my $r3 = sprintf "%.3f", (abs($rr3));

if (($r1 <= $j) && ($r2 <= $j) && ($r3 <= $j))
        {
    my $r_sq1 = $r1 * $r1;
    my $r_sq2 = $r2 * $r2;
    my $r_sq3 = $r3 * $r3;
    my $rsum = ($r_sq1 + $r_sq2 + $r_sq3);
    #print FILEHANDLE "$a1\t$aa1\n";
    print FILEHANDLE "$a1\t$a2\t$a3\t$r1\t$r2\t$r3\n";

        }

if ($k == $#queryx)
{
    exit;
}

if ($i == $ss)
{
    $k = $k + 1;
    $a1  = $queryx[$k];
    $a2 = $queryx[$k+1];
    $a3 = $queryx[$k+2];
    print "$a1\t$a2\t$a3\n";
    next;
}


$i++;
} 
    
close (FILEHANDLE);
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