#!/usr/bin/perl -w
#GIDgiver.pl

#this script reads gene symbols and assigns the matching Entrez GeneID to each gene


use strict;

open FH1, 'GID_GeneSymbol.txt', or die "Can't open GID file\n";
open FH2, 'CVD_genelist.txt', or die "Can't open CVD gene list\n";


our (@list1, @list2, @temp);
my %GID = ();
my %CVDgenes = ();

while (<FH1>){
	chomp;
	push (@list1, $_);
	foreach (@list1){
	@temp=split(/\s+/, $_);
	}
	%GID = map { $temp[0] => $temp[1] } @temp;

}

while (<FH2>){
	chomp;
	push (@list2, $_);
	}
	%CVDgenes = map { $_ => 1 } @list2;


while ((my $k, my $v) = each(%GID)) {
	if  (exists ($CVDgenes{$v})){
	print "The GID for gene $v is $k\n";
}}