function week(){
	document.getElementById("week_free").onclick = function week_of_day(){
		document.getElementById("day_of_week").disabled = !this.checked;
	}
		
	document.getElementById("week_all").onclick = function week_of_day(){
		document.getElementById("day_of_week").disabled = this.checked;
	}
	document.getElementById("weekday").onclick = function week_of_day(){
		document.getElementById("day_of_week").disabled = this.checked;
	}
	document.getElementById("weekend").onclick = function week_of_day(){
		document.getElementById("day_of_week").disabled = this.checked;
	}
}