var leftVal = (window.screen.width  - 626) / 2;
var topVal = (window.screen.height - 436) / 2;
function fb_click(u, t) {
	var url = 'http://www.facebook.com/sharer.php?u='+u+'&t='+t;
	window.open(url,'sharer','toolbar=0,status=0,width=626,height=436,left='+leftVal+',top='+topVal);
	return false;
}
function twt_click(u, t) {
	var url = 'http://twitter.com/share?text='+ t+'&url='+u;
	window.open(url,'sharer','toolbar=0,status=0,width=626,height=436,left='+leftVal+',top='+topVal);
	return false;
}
function google_click(u, t) {
	var url = 'https://plus.google.com/share?url='+u+'';
	window.open(url,'sharer','toolbar=0,status=0,width=626,height=436,left='+leftVal+',top='+topVal);
	return false;
}