function show_window(url) {
	var w = 550/2, h = 350/2, cw = w/2, ch = h/2;
	if (window.screen) {
	    w = Math.floor(screen.availWidth/2);
	    h = Math.floor(screen.availHeight/2);
	    cw = Math.floor((screen.availWidth-w)/2);
	    ch = Math.floor((screen.availHeight-h)/2);
	}
	window.open(url,'hotel','width=550,height=350,top='+ch+',left='+cw);
}

function currency(amount) {
	vysledek = ((document.forms.rates.currencyFrom.value * amount) / document.forms.rates.currencyTo.value);
	document.forms.rates.amountFrom.value = amount;
	document.forms.rates.amountTo.value = Math.round(vysledek);
}

function currency1(amount) {
	vysledek = ((document.forms.rates.currencyTo.value * amount) / document.forms.rates.currencyFrom.value);
	alert(amount + ' EUR\n     =\n' + Math.round(vysledek) + ' CZK');
}