#!/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
$A=0;$T=0;
while ($str=~ /A/ig) {$A++;# Line 4
print RESULT "\n A=$A ends at ",pos $str,"\n";}
while ($str=~ /T/ig) {$T++;
print RESULT "\n T=$T ends at ",pos $str,"\n";}
close(RESULT);                    # Line 17  
exit;