function lommeregner(){
	var pris = 0;
	var variant_exists = eval(document.getElementById('variant_antal_id'));
	if(variant_exists){
		pris = pris + document.getElementById('variant_pris_id').value * document.getElementById('variant_antal_id').value;
	}
	
	var hynde_exists = eval(document.getElementById('hynde_antal_id'));
	if(hynde_exists){
		pris = pris + document.getElementById('hynde_pris_id').value * document.getElementById('hynde_antal_id').value;
	}
	
	var hover_exists = eval(document.getElementById('hover_antal_id'));
	if(hover_exists){
		pris = pris + document.getElementById('hover_pris_id').value * document.getElementById('hover_antal_id').value;
	}
	
	var over_exists = eval(document.getElementById('over_antal_id'));
	if(over_exists){
		pris = pris + document.getElementById('over_pris_id').value * document.getElementById('over_antal_id').value;
	}

	var lomme_exists = eval(document.getElementById('lommeregner_pris_id'));
	if(lomme_exists){
		document.getElementById('lommeregner_pris_id').innerHTML = 'DKK ' + pris.toFixed(2) + '';
	}
}
setInterval("lommeregner()",1000);