c++初始化列表构造

#include <iostream>
#include <string>
using namespace std;
class Car {
public:
	string brand;
	int year;
	string type;
	//无参构造函数
	Car (){
		cout << "无参构造函数"<<endl;
	}
	//带一个参数的构造函数
	Car(string b)
	{
		cout <<"带一个参数的构造函数"<<endl;
		brand=b; 
	 } 
	 //带参数的构造函数
	Car(string b,int a)
	{
		cout <<"带参数的构造函数"<<endl;
		brand=b; 
		year=a;
	 } 
	//参数列表的方式进行构造
	Car(string b,int a,string t):brand(b),year(a),type(t){
		cout << "参数列表构造"<<endl; 
	}
	
	
	void display()
	{
		cout << "brand:"<<brand<<endl<<"year:"<<year<<endl; 
	}
	
	void displayall()
	{
		cout << "brand:"<<brand<<endl<<"year:"<<year<<"type:"<<type<<endl; 
	}
};

int main()
{
	Car car1;
	car1.brand="xiaomi";
	car1.year=1;
	car1.display();
	
	Car car2("baoma",20);
	car2.display();
	
	Car car3("qirui",10,"new");
	car3.displayall();
	
	Car *pcar=new Car("byd",30);
	pcar->display();
	return 0;
	
}