2021-11-05 C++结构体方面的知识

C++ 结构体方面的知识

1 基础语法

1.1 创建结构体变量，三种方法

#include<iostream>
using namespace std;

//1. 创建学生数据类型
//自定义数据类型，一些类型集合组成的一个类型
struct student
{
	//学生类型
	string name;
	int age;
	int score;
};

int main()
{
//2. 通过学生类型创建具体学生
	// 2.1
	// struct 关键字可以在创建变量的时候省略
	struct student s1;
	s1.age = 19;
	s1.name = "穆久涛";
	s1.score = 100;
	cout << "姓名" << s1.name << "年龄" 
		<< s1.age << "分数" << s1.score<< endl;
	

	// 2,2  struct student s1 ={...}
	struct student s2 = { "穆久涛", 19, 80 };
	cout << "姓名" << s1.name << "年龄"
		<< s1.age << "分数" << s1.score << endl;

	// 2.3
	// 在定义结构体时候创建结构体变量
	struct student
	{
		//学生类型
		string name;
		int age;
		int score;
	}s3;
	s3.name = "礼拜";
	s3.age = 11;
	s3.score = 22;
	return 0;
	system("pause");
}

1.2 修改结构体数组内容，遍历内容

#include<iostream>
using namespace std;

//1. 定义结构体
struct student
{
	//学生类型
	string name;
	int age;
	int score;
};

int main()
{
	//2. 创建结构体数组
	struct student stuarray[3] =
	{
		{"穆久涛",19,  99},
		{"李四",22,  89},
		{"王五",19,  77},
	};
	//3. 给结构体数组中的元素赋值, 修改其中的值
	stuarray[2].age = 44;
	stuarray[2].name = "别杀我";
	stuarray[2].score = 44;
	//4. 遍历结构体数组
	for (int i = 0; i < 3; i++)
	{
		cout << "姓名" << stuarray[i].name
			<< "年龄" << stuarray[i].age
			<< "分数" << stuarray[i].score << endl;
	}
	return 0;
	system("pause");
}

1.3 结构体指针的用法

#include<iostream>
using namespace std;

// 利用操作符 ->  访问结构体属性
//1. 定义结构体
struct student
{
	//学生类型
	string name;
	int age;
	int score;
};


int main()
{
	//2. 创建结构体数组
	struct student stuarray = { "穆久涛",19,  99 };
	// 通过指针指向结构体变量
	student * p = &stuarray;   // auto = student 
	// 通过指针访问结构体变量中的数据
	cout << p->name << endl;
	//通过结构体指针访问结构体中的变量
	return 0;
	system("pause");
}

1.4 嵌套结构体的使用

#include<iostream>
using namespace std;

//定义学生的结构体
struct student
{
	//学生类型
	string name;
	int age;
	int score;
};

//定义老师的结构体
struct teacher
{
	//老师类型
	int id;
	string name;
	int age;
	struct student stu; //辅导的学生
};

int main()
{
	//结构体嵌套结构体
	//创建老师
	teacher t;
	t.id = 1000;
	t.age = 40;
	t.name = "老王";
	t.stu.age = 18;
	t.stu.name = "小王";	
	t.stu.score = 99;

	cout << t.name << t.age << t.stu.name << endl;

	return 0;
	system("pause");
}

1.5 结构体作函数参数

#include<iostream>
using namespace std;

//定义学生的结构体
struct student
{
	//学生类型
	string name;
	int age;
	int score;
};
//打印学生信息函数
//1. 值传递
void printstudent1(student s)
{
	s.age = 999;  //只会在函数中修改
	cout << "姓名" << s.name << "年龄"
		<< s.age << "分数" << s.score << endl;
}
//2. 地址传递
void printstudent2(student *s)
{
	cout << "姓名" << s->name << "年龄"
		<< s->age << "分数" << s->score << endl;
}
int main()
{
	//将结构体作为函数参数
	//将学生传入到一个参数中，打印学生身上的所有图片

	//创建结构体变量
	struct student s;
	s.score = 100;
	s.age = 40;
	s.name = "老王";
	printstudent1(s);
	printstudent2(&s);

	cout << "姓名" << s.name << "年龄"
		<< s.age << "分数" << s.score << endl;

	return 0;
	system("pause");
}

1.6 结构体中const的使用场景

#include<iostream>
using namespace std;

//定义学生的结构体
struct student
{
	//学生类型
	string name;
	int age;
	int score;
};

//打印学生信息函数
//1. 地址传递;  不会增加内存信息good！！！！！！
void printstudent1(const struct student *s)  //const !!!!!!!!!!!!!
{
	// s->age = 999;  //只会在函数中修改  // 加上const之后就不能修改了
	cout << "姓名" << s.name << "年龄"
		<< s.age << "分数" << s.score << endl;
}

int main()
{
	//将结构体作为函数参数
	//将学生传入到一个参数中，打印学生身上的所有图片
	//创建结构体变量
	struct student s;
	s.score = 100;
	s.age = 40;
	s.name = "老王";
	printstudent1(&s);
	return 0;
	system("pause");
}

2 三个结构体相关的案例

2.1 三个老师带着五个学生的案例

#include<iostream>
using namespace std;
struct student 
{
	string sname;
	int age;
	int score;
};

//定义老师的结构体
struct teacher
{
	//老师类型
	string tname;
	struct student stu[5];
};

void allocatespace(struct teacher tea[3],int len)
{
	string Q = "ABCDE";
	for (int i = 0; i < 3; i++)
	{
		tea[i].tname = "teacher_";
		tea[i].tname += Q[i];

		for (int j = 0; j < 5; j++)
		{
			tea[i].stu[j].score = rand() % 61 + 40;
			tea[i].stu[j].age = rand() % 21;
			tea[i].stu[j].sname = "student_";
			tea[i].stu[j].sname += Q[j];
		}
	}
}

void printarray(struct teacher tea[])
{
	for (int i = 0; i < 3; i++)
	{
		cout << "老师姓名为：" << tea[i].tname << "这个老师带的学生为：" << endl;
		for (int j = 0; j < 5; j++)
		{
			cout << "学生姓名为 ：" << tea[i].stu[j].sname 
				<< " 学生年龄为：" << tea[i].stu[j].age 
				<< " 学生成绩为：" << tea[i].stu[j].score << endl;
		}
	}
}
int main()
{
	//1.定义结构体
	struct teacher tea[3];
	//2.填入数据
	int len = 3;
	allocatespace(tea, len);
	//3. 输出数据
	printarray(tea);
	return 0;
	system("pause");
}

2.2 对结构体数组进行比较，冒泡排序

#include<iostream>
using namespace std;

//定义英雄的结构体
struct hero
{
	//英雄类型
	string tname;
	int age;
	string sex;
};

void compare(struct hero h[])
{
	for (int i = 0; i < 5-1; i++)
	{
		for (int j = 0; j < 5-i - 1; j++)
		{
			if (h[j].age < h[j + 1].age)
			{
				struct hero temp = h[j];
				h[j] = h[j + 1];
				h[j + 1] = temp;
			}
		}
	}
}

void printarray(struct hero h[5])
{
	for (int i = 0; i < 5; i++)
	{
		cout << "英雄姓名：" << h[i].tname
			<< " 英雄年龄：" << h[i].age
			<< " 英雄性别: " << h[i].sex << endl;
	}
}

int main()
{
	//1.定义结构体
	struct hero h[5] =
	{
		{"刘备",23,"男"},
		{"张飞",27,"男"},
		{"相遇",33,"男"},
		{"赵云",43,"男"},
		{"李白",13,"男"},
	};
	//3. 进行比较
	compare(h);
	//2. 输出数据
	printarray(h);
	return 0;
	system("pause");
}

2.3 通讯录管理系统

通讯录是一个可以记录亲人、好友信息的工具。

·1添加联系人︰向通讯录中添加新人，信息包括（姓名、性别、年龄、联系电话、家庭住址）最多记录1000人·
·2显示联系人:显示通讯录中所有联系人信息
·3删除联系人:按照姓名进行删除指定联系人
·4查找联系人:按照姓名查看指定联系人信息
·5修改联系人:按照姓名重新修改指定联系人
·6清空联系人:清空通讯录中所有信息
·0退出通讯录:退出当前使用的通讯录

#include<iostream>
using namespace std;
#define MAX 1000
void showmenu()
{
	cout << "**********************" << endl;
	cout << "*****1.添加联系人*****" << endl;
	cout << "*****2.显示联系人*****" << endl;
	cout << "*****3.删除联系人*****" << endl;
	cout << "*****4.查找联系人*****" << endl;
	cout << "*****5.修改联系人*****" << endl;
	cout << "*****6.清空联系人*****" << endl;
	cout << "*****0.退出通讯录*****" << endl;
}
struct person
{
	string m_name;
	int m_sex;
	int m_age;
	string m_phone;
};
struct addressperson
{
	struct person personarray[MAX];
	int m_size;
};
//   1 添加联系人
void addperson(struct addressperson *abs)
{
	if (abs->m_size == MAX)
	{
		cout<<"达到最大值，别再输入了" << endl;
	}
	else
	{
		//输入姓名
		cout<<"请输入姓名" << endl;
		string name;
		cin >> name;
		abs->personarray[abs->m_size].m_name = name;  %% abs是结构体指针，他只会指向它内部的m_size和personarray！！

		cout << "请输入性别" << endl;
		cout << "1--男人" << endl;
		cout << "2--女人" << endl;
		int sex = 0;
		cin >> sex;

		if (sex == 1 || sex == 2)
		{
			abs->personarray[abs->m_size].m_sex = sex;
		}

		cout << "请输入年龄" << endl;
		int age = 0;
		cin >> age;
		abs->personarray[abs->m_size].m_age = age;

		cout << "请输入电话" << endl;
		int phone;
		cin >> phone;
		abs->personarray[abs->m_size].m_phone = phone;

		//更新人数
		abs->m_size++;
		system("pause");
		system("cls");
	}
}
//  2 显示联系人
void showperson(struct addressperson* abs)
{
	if (abs->m_size == 0)
	{
		cout << "通讯录一个人也没有" << endl;
	}
	else
	{
		for (int i = 0; i < abs->m_size; i++)
		{
			cout <<"姓名："  << abs->personarray[i].m_name << "\t";
			if (abs->personarray[i].m_sex == 1)
			{
				cout<<"性别：男" << endl;
			}
			else
			{
				cout<<"性别：女" << endl;
			}
			cout << "年龄：" << abs->personarray[i].m_age << "\t";
			cout << "电话：" << abs->personarray[i].m_phone << endl;
		}
		system("pause");
		system("cls");
	}
}
// 3 删除联系人
int isexist(struct addressperson* abs, string name)
{
	for (int i = 0; i < abs->m_size; i++)
	{
		if (abs->personarray[i].m_name == name)
		{
			return i;
		}
	}
	return -1;
}
void deleteperson(struct addressperson* abs)
{
	cout<<"请输入你要删除的联系人" << endl;
	string name;
	cin >> name;
	int ret = isexist(  abs, name);
	if (ret != -1)
	{
		//找到人了，进行删除操作
		for (int i = ret; i < abs->m_size; i++)
		{
			//数据前移,全部都前移
			abs->personarray[i] = abs->personarray[i + 1];
		}
		abs->m_size--; //更新通讯录的人数
	}
	else
	{
		cout << "查无此人" << endl;
	}
	system("pause");
	system("cls");
}
// 4. 查找联系人
void findperson(struct addressperson* abs)
{
	cout << "请输入你要查找的联系人的姓名" << endl;
	string name;
	cin >> name;
	int ret = isexist(abs, name);
	if (ret != -1)
	{
		cout << "姓名" << abs->personarray[ret].m_name << "\t";
		cout << "性别" << abs->personarray[ret].m_sex << "\t";
		cout << "年龄" << abs->personarray[ret].m_age << "\t";
		cout << "电话" << abs->personarray[ret].m_phone << endl;
	}
	else
	{
		cout << "查无此人" << endl;
	}
	system("pause");
	system("cls");
}
// 5 修改联系人
void modifyperson(struct addressperson* abs)
{
	cout << "请输入你要修改的联系人的姓名" << endl;
	string name;
	cin >> name;
	int ret = isexist(abs, name);
	if (ret != -1)
	{
		cout << "请输入姓名" << endl;
		string name;
		cin >> name;
		abs->personarray[ret].m_name = name;

		cout << "请输入性别" << endl;
		cout << "1--男人" << endl;
		cout << "2--女人" << endl;
		int sex = 0;
		cin >> sex;

		if (sex == 1 || sex == 2)
		{
			abs->personarray[ret].m_sex = sex;
		}

		cout << "请输入年龄" << endl;
		int age = 0;
		cin >> age;
		abs->personarray[ret].m_age = age;

		cout << "请输入电话" << endl;
		int phone;
		cin >> phone;
		abs->personarray[ret].m_phone = phone;

		cout << "录入完毕" << endl;
	}
	else
	{
		cout << "查无此人" << endl;
	}
	system("pause");
	system("cls");

}
void cleanperson(struct addressperson* abs)
{
	abs->m_size = 0;
	cout<<"已经清空了" << endl;
	system("pause");
	system("clc");
}

int main() {
	struct addressperson abs;
	abs.m_size = 0;
	while (true)
	{
		showmenu();
		cout << "请输入选项" << endl;
		int select = 0;
		cin >> select;
		switch (select)
		    {
			case 1:
				addperson(&abs);
				break;
			case 2:
				showperson(&abs);
				break;
			case 3:
				deleteperson(&abs);
				break;
			case 4:
				findperson(&abs);
				break;
			case 5:
				addperson(&abs);
				break;
			case 6:
				cleanperson(&abs);
				break;
			case 0:
				cout << "欢迎下次使用" << endl;
				system("pause");
				return 0;
				break;
			default:
				break;
		    }
	}
}