die "usage: perl $0 file_nm line_nb col_start col_end replacement \n" unless @ARGV;
die "Invalid number of arguments \nusage: perl $0 file_nm line_nb col_start col_end replacement \n" if @ARGV ne 5;

my ($file_nm,$line_nb,$col_start,$col_end,$string)=@ARGV;

chomp($content=`perl -ne "print if $. == ${line_nb}" $file_nm`); #get the specific line from file

chomp ($replacement=`perl -ne "substr($content, $col_start, $col_end, $string);print $content"`); #get the replaced line
#print "New content \n$content \n";
`perl -pi -e "s/$content/$replacement/" $file_nm`; #now substitute the whole line with the new replaced line

##</code><code>##

use File::Basename;
die "usage: perl $0 file_nm line_nb pos_start-pos_end replacement \n" unless @ARGV;
die "Invalid number of arguments \nusage: perl $0 file_nm line_nb pos_start pos_end replacement \n" if @ARGV ne 5;

my ($file_nm,$line_nb,$pos,$string)=@ARGV;
my ($pos_start,$pos_end)=split (/-/,$pos);
$file_nm=File::Basename::basename($file_nm);

open(READ_HN,"$file_nm") or die "Cant open $file_nm $! \n";
open(WRITE_HN,">${file_nm}.updated") or die "Cant write to ${file_nm}.updated $! \n";


#chomp($content=`perl -ne "print if $. == ${line_nb}" $file_nm`);
while(<READ_HN>)
{
	if ($. == $line_nb)
	{
		substr($_, $pos_start, $pos_end, $string);
	}
	print WRITE_HN "$_\n";
}


close(WRITE_HN);
close(READ_HN);