#!/usr/bin/perl -w
$str="BATCATDATEFEAT";
$A=0;$T=0;
while ($str=~ /A/ig) {$A++;# Line 4
print"\n A=$A ends at ",pos $str,"\n";}
while ($str=~ /T/ig) {$T++;
print"\n T=$T ends at ",pos $str,"\n";}
$output="Results .txt";                 # Line 8 
unless (open(RESULT,">$output")){
print"Cannot open file\"$output\".\n\n";
exit;                             # Line 11 
} # Line 12
print RESULT"\n A=$A ends at ",pos $str,"\n
 T=$T ends at ",pos $str,"\n\n"; 
close(RESULT);                    # Line 17  
exit;

##</code><code>##

Microsoft Windows [Version 6.1.7600]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\Users\xx>cd desktop
C:\Users\xx\Desktop>at.pl

 A=1 ends at 2

 A=2 ends at 5

 A=3 ends at 8

 A=4 ends at 13

 T=1 ends at 3

 T=2 ends at 6

 T=3 ends at 9

 T=4 ends at 14

Use of uninitialized value in print at C:\Users\DR-SUPRIYO\Desktop\at.pl line 13.
Use of uninitialized value in print at C:\Users\DR-SUPRIYO\Desktop\at.pl line 13.

##</code><code>##

A=4 ends at 

T=4 ends at