整理思维导图

课上类实现> 、<、!=、||、！和后自增、前自减、后自减运算符的重载

代码部分：

#include <iostream>
using namespace std;
class complex
{
    int rel;
    int vir;
public:
    complex(int rel,int vir):rel(rel),vir(vir){}
    complex(){}
    void show();
    complex operator+(complex other);
    complex operator-(complex other);
    complex operator*(complex other);
    complex operator/(complex other);
    bool operator==(const complex other);
    bool operator>(const complex other);
    friend bool operator&&(const complex c1,const complex c2);
    friend bool operator||(const complex c1,const complex c2);
    complex operator++();
    complex operator++(int);
    complex operator--();
    complex operator--(int);
};
//+
complex complex::operator+(complex other)
{
    complex temp;
    temp.rel=this->rel+other.rel;
    temp.vir=this->vir+other.vir;
    return  temp;
}
//-
complex complex::operator-(complex other)
{
    complex temp;
    temp.rel=rel+other.rel;
    temp.vir=vir+other.vir;
    return  temp;
}
//*
complex complex::operator*(complex other)
{
    complex temp;
    temp.rel=rel*other.rel;
    temp.vir=vir*other.vir;
    return  temp;
}
//  /
complex complex::operator/(complex other)
{
    complex temp;
    temp.rel=rel/other.rel;
    temp.vir=vir/other.vir;
    return  temp;
}
// ==
bool complex::operator==(const complex other)
{
    return this->rel==other.rel&&this->vir==other.vir;
}
// >
bool complex::operator>(const complex other)
{
    return this->rel>other.rel&&this->vir>other.vir;
}
//&&
bool operator&&(const complex c1,const complex c2)
{
    return (c1.rel||c1.vir)&&(c2.rel||c2.vir);
}
//||
bool operator||(const complex c1,const complex c2)
{
    return (c1.rel&&c1.vir)||(c2.rel&&c2.vir);
}
//前++
complex complex::operator++()
{
    this->rel=this->rel+1;
    this->vir=this->vir+1;
    return *this;
}
//后++
complex complex::operator++(int)
{
    complex temp;
    temp.rel=this->rel;
    temp.vir=this->vir;
    this->rel=this->rel+1;
    this->vir=this->vir+1;
    return temp;
}
//前--
complex complex::operator--()
{
    complex temp;
    temp.rel=--(this->rel);
    temp.vir=--(this->vir);
    return  temp;
}
//后--
complex complex::operator--(int)
{
    complex temp;
    temp.rel=this->rel;
    temp.vir=this->vir;
    this->rel=this->rel-1;
    this->vir=this->vir-1;
    return temp;
}
void complex::show()
{
    cout << rel << "+" << vir << "i" << endl;

}
int main()
{
    int num1=12,num2=28;
    num2=num1+num2;
    complex c1(num1,num2);
    complex c2(8,2);
    complex c3=c1.operator+(c2);
    c3=c1-c2;
    c3=c1*c2;
    c3=c1/c2;
    c3.show();
    cout << (c3==c2) << endl;
    cout << (c3>c2) <<  endl;
    cout << "c1&&c2?" << endl;
    cout << (c1&&c2) << endl;
    cout << "c1||c2?" << endl;
    cout << (c1||c2) << endl;
    complex c4(1,1);
    complex c6(1,1);
    complex c5(2,2);
    c5=c6+(c4++);
    c5.show();
    --c5;
    c5.show();
    c5--;
    c5.show();
    return 0;
}

效果图：

实现昨天作业中My_string类中的+，==，>运算符重载

代码部分：

#include <iostream>
#include <cstring>
using namespace std;
char c = '\0';
class My_string
{
    char *str;     //记录C风格的字符串
    int size;      //记录字符串长度
public:
    //无参构造
    My_string():str(new char('\0')),size(0){cout << "My_string的无参构造" << endl;}
    //有参构造
    My_string(const char *p):str(new char[strlen(p)+1]),size(strlen(p))
    {
        strcpy(str,p);
        cout << "My_string的有参构造" << endl;
    }
    //拷贝构造
    My_string(const My_string &other):str(new char[other.size+1]),size(other.size)
    {
        strcpy(str,other.str);   //完成两个类对象字符串内容的拷贝
        cout << "拷贝构造" << endl;
    }
    //拷贝赋值
    My_string &operator=(const My_string &other)
    {
        //先把目标类对象指针原来指向的堆地址释放
        delete this->str;
        str = new char[other.size+1];   //申请新的能容纳下other类对象字符串的空间
        strcpy(str,other.str);    //拷贝字符串
        this->size = other.size;
        //返回自身的引用
        return *this;
    }
    //析构函数
    ~My_string()
    {
        delete []str;   //释放str指向的多个空间
    }
    //at函数
    char &my_at(int num);  //可以判断访问是否合法
    My_string operator+(My_string &other);
    bool operator>(My_string &other);
    bool operator==(My_string &other);
};
char &My_string::my_at(int num)
{
    if(num<0||num>=this->size)
    {
        cout << "访问越界" << endl;
        return c;
    }
    return str[num];
}
// +
My_string My_string::operator+(My_string &other)
{
    My_string temp;
    strcat(this->str,other.str);
    temp.size=this->size+other.size;
    return  temp;
}
//  ==
bool My_string::operator==(My_string &other)
{
    return this->size==other.size;
}
// >
bool My_string::operator>(My_string &other)
{
    return this->size>other.size;
}
int main()
{
    My_string s1 = "hello";
    My_string s2 = "world!";
    My_string s3 = s2;
    s1.my_at(0) = 'a';
    cout << s1.my_at(0) << endl;
    s1 = s2;


}