use strict;
use warnings;
open (RD, "input.txt") or die;
my @Read = <RD>; close (RD);

open (WR2, ">>output.txt") or die;
my $count=0;
my $C="2001-1041";
my $found=0;#######Temporary variable to find the content in whole file
for (my $read=0; $read <= $#Read; $read++)
{
    if($Read[$read] =~ /$C/)
    {
    	$count++;$found++;    	
    }    
}
print WR2"$count=$C\n" unless($found);

##</code><code>##

use strict;
use warnings;
open (RD, "input.txt") or die;
open (WR2, ">>output.txt") or die;
my $count=0;
my $C="2001-1041";
my $found=0;#######Temporary variable to find the content in whole file
while(<RD>){
    if($_ =~ /$C/)
    {
    	$count++;$found++;    	
    }    
}
print WR2"$count=$C\n" unless($found);

##</code><code>##

use strict;
use warnings;

open (RD, "input.txt") or die;
my $input;
do{
local undef $/; ######To undef the input record separator '$/'
$input=<RD>;
}; #####To read the whole file in single scalar variable

open (WR2, ">>output.txt") or die;
my $count=0;
my $C="2001-1041";

while($input =~ /$C/g)
{
	$count++;	
}
print WR2 "$count=$C\n" unless($count);