SOURCE

		var order500 = function(orderType,pay,stock){
			if(orderType === 1 && pay ===true){
				console.log('500元定金预购,得到100元优惠券')
			}else{
				order200(orderType,pay,stock)
			}
		}

		var order200 = function(orderType,pay,stock){
			if(orderType === 2 && pay ===true){
				console.log('200元定金预购,得到50元优惠券')
			}else{
				orderNormal(orderType,pay,stock)
			}
		}

		var orderNormal	= function(orderType,pay,stock){
			if(stock > 0){
				console.log('普通购物,无优惠券')
			}else{
				console.log('手机库存不足')
			}
		}

		order500(1,true,500)
		order500(1,false,500)
		order500(2,true,500)
		order500(3,true,500)