#!/usr/local/bin/perl

open (FASTAFILE, 'human_fold_25.txt');

$sequence = ' ';
$Ccount = 0;
$Gcount = 0;
$identifier = ' ';

while ($line = <FASTAFILE>) {
	chomp $line;
	
	if ( $line =~ /^>/ ) {
		$identifier = $line;
	} elsif ( $line =~ /^\./ ) {
		next;
	} elsif ( $line =~ /^\(/ ) {
	}else {
		$sequence = $line;
	}
}

$sequencelength = length ($sequence);

@nucleotides = split ( '' , $sequence );

foreach $nuc (@nucleotides) {
	if ( $nuc eq 'G') {
		$Gcount = $Gcount + 1;
	} elsif ( $nuc eq 'C') {
		$Ccount = $Ccount + 1;
	}
}

$GCcontent = ((( $Gcount + $Ccount )/ $sequencelength ) * 100);

close (FASTAFILE);

print "$identifier", ", ", "$GCcontent\n"