My_string 运算符重载，My_stack

思维导图

将My_string类中的所有能重载的运算符全部进行重载

+、[] 、>、<、==、>=、<=、!= 、+=（可以加等一个字符串，也可以加等一个字符）、输入输出(<< 、 >>)

My_string

my_string.h

#ifndef MY_STRING_H
#define MY_STRING_H#include <iostream>
#include <cstring>using namespace std;class My_string
{
private:char *ptr;         //指向字符数组的指针int size;           //字符串的最大容量int len;            //字符串当前容量public://无参构造My_string():size(20){cout<<"****************无参构造***********"<<endl;this->ptr = new char[size];this->ptr[0] = '\0';            //表示串为空串this->len = 0;}//有参构造My_string(const char* src){cout<<"****************一个参数有参构造***********"<<endl;this->len = strlen(src);this->size = len + 1;this->ptr = new char[size];strcpy(this->ptr,src);}My_string(int num,char value){cout<<"****************两个参数有参构造***********"<<endl;this->len = num;this->size = len + 1;this->ptr = new char[len+1];int i=0;while(i<num){this->ptr[i]=value;i++;}this->ptr[num]='\0';}//拷贝构造My_string (const My_string &other){cout<<"****************拷贝构造***********"<<endl;len = other.len;size = other.size;ptr = new char[size];strcpy(ptr, other.ptr);}//拷贝赋值My_string &operator=(const My_string &other){cout<<"****************拷贝赋值***********"<<endl;if (this == &other) {return *this;  // 直接返回当前对象}delete[] ptr;this->len = other.len;this->size = other.size;this->ptr = new char[size];strcpy(ptr, other.ptr);return *this;}//析构函数~My_string(){cout<<"****************析构函数***********"<<endl;delete []this->ptr;}//显示内容void show();//判空void isempty();//判满void isfull();//尾插void push_back(char value);//尾删void pop_back();//at函数实现char &at(int index);//清空函数void clear();//返回C风格字符串char* data();//返回实际长度int get_length();//返回当前最大容量int get_size();//君子函数:二倍扩容void resize();//自定义运算符重载 +const My_string operator+(const My_string &R){My_string temp;while(this->len+R.len>this->size){resize();}strcpy(temp.ptr,this->ptr);temp.ptr = strcat(temp.ptr,R.ptr);this->len = R.len+this->len;return temp;}//自定义运算符重载 []char  operator[](int n){return ptr[n];}// 重载大于运算符 (>)// 用于比较两个 My_string 对象，逐字符比较bool operator>(const My_string &R) const {int i = 0;// 逐字符比较当前对象和传入的对象，直到遇到字符串结束符 '\0'while (this->ptr[i] != '\0' && R.ptr[i] != '\0') {if (this->ptr[i] > R.ptr[i]) {// 如果当前对象的字符大于传入对象的字符，则返回 truereturn true;} else if (this->ptr[i] < R.ptr[i]) { // 如果当前对象的字符小于传入对象的字符，则返回 falsereturn false;}i++;}if (this->ptr[i] != '\0' && R.ptr[i] == '\0') {// 如果当前对象的字符串未结束，而传入对象的字符串已结束，返回 truereturn true;}return false;}// 重载小于运算符 (<)bool operator<(const My_string &R) const {return strcmp(this->ptr, R.ptr) < 0;}// 重载小于等于运算符 (<=)bool operator<=(const My_string &R) const {return strcmp(this->ptr, R.ptr) <= 0;}// 重载大于等于运算符 (>=)bool operator>=(const My_string &R) const {return strcmp(this->ptr, R.ptr) >= 0;}// 重载相等运算符 (==)bool operator==(const My_string &R) const {return strcmp(this->ptr, R.ptr) == 0;}// 重载不等运算符 (!=)bool operator!=(const My_string &R) const {return strcmp(this->ptr, R.ptr) != 0;}// 重载 += 运算符，用于将传入的字符串附加到当前字符串后My_string& operator+=(const My_string &R) {// 检查当前字符串的容量是否足够容纳新字符串，如果不够则调用 resize 扩展容量while (this->len + R.len >= this->size) {this->resize();}// 使用 strcat 将传入对象的字符串附加到当前对象的字符串后strcat(this->ptr, R.ptr);// 更新当前字符串的实际长度this->len = this->len + R.len;// 返回当前对象return *this;}// 重载输出运算符 <<friend ostream& operator<<(ostream &L, const My_string &R);};#endif // MY_STRING_H

my_string.cpp

#include "my_string.h"
#include <cstring>
void My_string::show(){cout<<ptr<<endl;
}
//判空
void My_string::isempty(){if(this->len==0){cout<<"字符串为空"<<endl;}return;
}
//判满
void My_string::isfull(){if(this->len>=this->size){cout<<"字符串满"<<endl;resize();cout<<"重新分配空间"<<endl;}else{cout<<"字符串未满"<<endl;}return;
}//尾插
void My_string::push_back(char value){this->isfull();this->ptr[len]=value;len++;ptr[len]='\0';
}//尾删
void My_string::pop_back(){this->len=this->len-1;ptr[len]='\0';
}
//at函数实现
char & My_string::at(int index){return ptr[index];
}
//清空函数
void My_string::clear(){ptr[0]='\0';this->len=0;
}//返回C风格字符串
char* My_string::data(){return this->ptr;  // 返回指向字符串的指针
}
//返回实际长度
int My_string::get_length(){return this->len;
}
//返回当前最大容量
int My_string::get_size(){return this->size;
}//君子函数:二倍扩容
void My_string::resize() {size *= 2;char* new_ptr = new char[size];strcpy(new_ptr, ptr);delete[] ptr;ptr = new_ptr;}ostream & operator<<(ostream &L,const My_string &R){L<<R.ptr;return L;
}

main.cpp

#include "my_string.h"int main(){My_string s1("ABCDEF");My_string s2("GHIJK");//重构 + 运算符My_string s3 = s1+s2;s3.show();//重构 [] 运算符cout<<s3[2]<<endl;cout<<"s1:"<<s1<<"   s2:"<<s2<<endl;//重构 > 运算符cout<<"s1"<<">"<<"s2?"<<endl;if(s1>s2){cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}//重构 < 运算符cout<<"s1"<<"<"<<"s2?"<<endl;if(s1<s2){cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}//重构 <= 运算符cout<<"s1"<<"<="<<"s2?"<<endl;if(s1<=s2){cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}//重构 >= 运算符cout<<"s1"<<">="<<"s2?"<<endl;if(s1>=s2){cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}//重构 == 运算符cout<<"s1"<<"=="<<"s2?"<<endl;if(s1==s2){cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}//重构 != 运算符cout<<"s1"<<"!="<<"s2?"<<endl;if(s1!=s2){cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}//重构 += 运算符cout<<"************************"<<endl;s1.show();s2.show();s1+=s2;s1.show();//重构<<运算符cout<<s1<<endl;}

仿照stack类实现my_stack,实现一个栈的操作

Mystack

My_stack.cpp

#include"My_stack.h"
using namespace std;
// 入栈操作
void My_Stack::push(int value) {if (top>=MAX_SIZE - 1) {cout<<"栈满!"<< value<<endl;return;}arr[++top] = value;  // 增加栈顶并赋值cout<<"入栈: "<<value<<endl;
}// 出栈操作
int My_Stack::pop() {if (isEmpty()) {cout << "栈空！" << endl;return -1;  // 返回 -1 作为错误指示}int pop = arr[top--];  // 返回栈顶值并减少栈顶索引cout << "出栈: " << pop << endl;return pop;
}// 获取栈顶元素
int My_Stack::peek() {if (isEmpty()) {cout << "栈空！" << endl;return -1;}return arr[top];  // 返回栈顶值
}// 判断栈是否为空
bool My_Stack::isEmpty() {return top == -1;  //则栈为空，栈顶索引为 -1
}// 获取栈的当前大小
int My_Stack::size() {return top + 1;  // 返回栈中元素的个数
}
void My_Stack::swap_t(My_Stack& other) {// 交换栈顶索引swap(top, other.top);// 交换栈中的内容for (int i = 0; i < MAX_SIZE; ++i) {swap(arr[i], other.arr[i]);}
}
// 显示栈中的内容
void My_Stack::show() {if (isEmpty()) {cout << "栈空！" << endl;return;}cout << "栈中的元素: ";for (int i = 0; i <= top; ++i) {cout << arr[i] << " ";  // 打印每个元素}cout << endl;
}

My_stack.h

#ifndef MY_STACK_H
#define MY_STACK_H
#include <iostream>using namespace std;class My_Stack {
private:static const int MAX_SIZE = 100;  // 定义栈的最大容量int arr[MAX_SIZE];  // 数组用于存储栈元素int top;  // 栈顶索引public:My_Stack():top(-1){}  // 构造函数My_Stack(const My_Stack& other):top(other.top) {//拷贝构造函数for (int i = 0; i <= top; ++i) {arr[i] = other.arr[i];  // 深拷贝}}~My_Stack(){}void push(int value);  // 入栈操作int pop();  // 出栈操作int peek();  // 获取栈顶元素bool isEmpty();  // 判断栈是否为空int size();  // 获取栈的当前大小void swap_t(My_Stack& other);void show();  // 显示栈中的内容My_Stack& operator=(const My_Stack& other){  // 赋值操作符重载if (this != &other) {  // 自我赋值检查top = other.top;  // 复制栈顶索引for (int i = 0; i <= top; ++i) {arr[i] = other.arr[i];  // 深拷贝}}return *this;  // 返回当前对象的引用}
};#endif // MY_STACK_H

main.cpp

#include "My_stack.h"int main() {// 创建第一个栈并进行入栈操作My_Stack s1;s1.push(10);s1.push(20);s1.push(30);// 创建第二个栈并进行入栈操作My_Stack s2;s2.push(40);s2.push(50);My_Stack s3 = s2;cout<<"s3:";s3.show();cout <<"交换前:"<< endl;cout<<"s1:";s1.show();cout<<"s2:";s2.show();// 交换s1和s2的内容s1.swap_t(s2);cout << "交换后:" << endl;cout<<"s1:";s1.show();cout<<"s2:";s2.show();// 出栈cout<<"从 s1 弹出元素: "<<s1.pop()<<endl;cout<<"从 s2 弹出元素: "<<s2.pop()<<endl;// 检查栈的大小cout<<"s1 当前大小: "<<s1.size()<<endl;cout<<"s2 当前大小: "<<s2.size()<<endl;// 再次弹出元素s1.pop();s2.pop();cout << "交换后再次弹出后的大小:" << endl;cout << "s1 当前大小: " << s1.size() << endl;cout << "s2 当前大小: " << s2.size() << endl;return 0;
}