#!usr/bin/perl 
print "\n\nPlease type the filename of the DNA sequence data: ";
$DNAfilename=<STDIN>;
chomp $DNAfilename;
unless ( open(DNAFILE, $DNAfilename) ) {
	print "Cannot open file \"$DNAfilename\"\n\n";
exit;
}
while(@DNA= <DNAFILE>) {
	$DNA=join('',@DNA);
close DNAFILE;
# Remove whitespace
$DNA=~ s/\s//g;
# Remove whitespace
$DNA=~ s/\s//g;# Line 15
# Count number of bases
$b=length($DNA);
print "\nNumber of bases: $b.\nDoes the value tally with GenBank record? If yes,continue.";
# Count number of each base and nonbase
$A=0;$T=0;$G=0;$C=0;$e=0; # Line 20
while($DNA=~ /A/ig){$A++}
while($DNA=~ /T/ig){$T++}
while($DNA=~ /G/ig){$G++}
while($DNA=~ /C/ig){$C++}
while($DNA=~ /[^ATGC]/ig){$e++} 
# Line 25
print "\nA=$A; T=$T; G=$G; C=$C; Errors(N)=$e.\n.";
}
exit;