C++重载类型

#include <iostream>#include <string>#include <vector>#include <list>using namespace std;class Date {public:  Date(int x, int y)    : x_(x)    , y_(y) {  }  void Print() {    cout << x_ << " : " << y_ << endl;  }private:  int x_;  int y_;};class Point {public:  Point(int x, int y)     : x_(x)    , y_(y) {  }  operator int() {    return x_ + y_;  }  //operator bool() {  //  return true;  //}  operator Date() {    return Date(x_, y_);  }private:  int x_;  int y_;};int main1() {  Point point(1, 2);  cout << point << endl;  cout << (int)point << endl;  Date date = (Date)point;  date.Print();  return 0;}