#include <iostream>
class A
{
public:
    A()  { cout << "A Constructor1" <<endl;
    A(int i) { x1=i;cout <<"A Constructor2" <<endl;
    void dispa() { cout << "x1=" << x1 <<endl;};
private:
    int x1;
    };
    class B :public A
    {
    public:
        B() {cout << "b Constructor1" <<endl;}
        B(int i): A(i+10) { x2=i;cout << "B Constructor2" <<endl;}
        void dispb()
        {
            dispb();
            cout << "x2=" <<x2<<endl;
        }
    private:
        int x2;
        };
        void main()
        {
            B b(2);
            b.dispb();
        }

最近看到派生构造函数了，但是这个程序怎么看也看不懂！还请大神给小友分析一下程序是咋运行的？？？