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);