function setEndDate() {
	var startDate = document.form.datawynajmu.value;
	var arrStartDate = startDate.split('-');
	if(arrStartDate.length!=3) return;
	var d = parseInt(arrStartDate[0]);
	var m = parseInt(arrStartDate[1])-1;
	var y = arrStartDate[2];
	var nd = new Date(y,m,d);
	//alert(nd);
	nd.setDate(d+1);

	var d = nd.getDate();
	var m = nd.getMonth()+1;
	var y = nd.getYear();
	d = d<10?'0'+d:d;
	m = m<10?'0'+m:m;

	document.form.datazwrotu.value = d+'-'+m+'-'+y;
}