C++中运算符（加号、减号、左移、递增、赋值、关系、函数调用）重载实例

#include <iostream>
#include <string>

using namespace std;

class Persion
{
  friend ostream& operator<<(ostream& out, Persion& p);
public:
  Persion()
  {

  }
  ~Persion()
  {
    if (c)
    {
      delete c;
    }
  }
  Persion(int a, int b)
  {
    this->a = a;
    this->b = b;
  }
  Persion(int a, int b, int c)
  {
    this->a = a;
    this->b = b;
    this->c = new int(c);
  }
  //加号运算符重载
  Persion operator+(const Persion p1)
  {
    Persion temp;
    temp.a = this->a + p1.a;
    temp.b = this->b + p1.b;
    return temp;
  }
  Persion operator+(const int p1)
  {
    Persion temp;
    temp.a = this->a + p1;
    temp.b = this->b + p1;
    return temp;
  }
  // 减号运算符重载
  Persion operator-(const Persion p1)
  {
    Persion temp;
    temp.a = this->a - p1.a;
    temp.b = this->b - p1.b;
    return temp;
  }
  //前置递增运算符重载
  Persion& operator++()
  {
    this->a += 1;
    this->b += 1;
    return *this;
  }
  //后置递增运算符重载
  Persion operator++(int)
  {
    Persion temp;
    temp.a = this->a;
    temp.b = this->b;

    this->a += 1;
    this->b += 1;
    return temp;
  }
  //赋值运算符重载(解决深浅拷贝问题)
  Persion& operator=(Persion& p)
  {
    this->a = p.a;
    this->b = p.b;
    if (this->c != NULL)
    {
      delete c;
      this->c = NULL;
    }
    this->c = new int(*p.c);
    return *this;
  }
  //关系运算符重载
  bool operator==(Persion &p)
  {
    if (this->a == p.a && this->b == p.b)
    {
      return true;
    }

    return false;
  }
  bool operator!=(Persion& p)
  {
    if (this->a == p.a && this->b == p.b)
    {
      return false;
    }

    return true;
  }
  //函数调用运算符重载(仿函数)
  void operator()()
  {
    cout << "a=" << this->a << "  b=" << this->b<<endl;
  }
  int operator()(int num)
  {
    return this->a + num;
  }

  int a;
  int b;
  int* c;
};
//左移运算符重载
ostream& operator<<(ostream &out,Persion &p)
{
  out << "a=" << p.a << "  b=" << p.b;
  return out;
}


int main()
{
  Persion p1(1, 1);
  Persion p2(2, 2);

  //加号运算符重载测试
  Persion p3 = p1+p2;
  cout <<"加号运算符重载测试：" << p3.a << endl;

  Persion p4 = p1 + 10;
  cout << "加号运算符重载测试：" << p4.a << endl;

  //减号运算符重载测试
  Persion p5 = p1 - p2;
  cout << "减号运算符重载测试：" << p5.a << endl;

  //左移运算符重载测试
  cout << "左移运算符重载测试：" << p5<< endl;

  //前置递增运算符重载测试
  Persion p6 = ++p5;
  cout << "前置递增运算符重载测试：" << p6 << endl;

  //后置递增运算符重载测试
  Persion p7 = (p5 ++)++;
  cout << "后置递增运算符重载测试：" << p7 << endl;

  //赋值运算符重载测试
  Persion p8( 8, 8, 8 );
  Persion p9;
  p9 = p8;
  cout << "赋值运算符重载测试：" << p8 << endl;
  cout << "赋值运算符重载测试：" << p9 << endl;

  //关系运算符重载测试
  cout << "关系运算符重载测试：" << (p9 == p8)<< endl;
  cout << "关系运算符重载测试：" << (p9 != p8) << endl;
  
  //函数调用运算符重载测试
  Persion p10;
  p10();
  cout << "函数调用运算符重载测试：" << p10 (20) << endl;

  return 0;
}