{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# C++的结构体" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# 1. 结构体" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "① 结构体属于用户自定义的数据类型，允许用户存储不同的数据类型。\n", "\n", "② 语法：struct 结构体名 { 结构体成员列表 }\n", "\n", "③ 通过结构体创建变量的方式有三种：\n", "\n", "1. struct 结构体名 变量名\n", "2. struct 结构体名 变量名 = { 成员1值，成员2值 }\n", "3. 定义结构体时顺便创建变量\n", "\n", "④ 结构体变量利用点.访问成员" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "//自定义数据类型，一些类型的集合组成一个类型\n", "//语法 struct 类型名称 { 成员列表 }\n", "//结构体定义的时候，struct关键字不能省略\n", "//1、创建学生数据类型：学生包括(姓名，年龄，分数)\n", "struct Student\n", "{\n", " //成员列表\n", "\n", " //姓名\n", " string name;\n", " //年龄\n", " int age;\n", " //分数\n", " int score;\n", "};\n", "\n", "int main()\n", "{\n", " //2.1 struct Student s1 s1类似结构体的实例值，类似变量赋值：int a = 10 → 属性 变量 变量值\n", " //结构体创建的时候，struct 关键字可以省略；上面结构体定义的时候 struct 可以省略\n", " struct Student s1;\n", " //给s1属性赋值，通过点.访问结构体变量中的属性\n", " s1.name = \"张三\";\n", " s1.age = 18;\n", " s1.score = 100;\n", "\n", " cout << \"姓名：\" << s1.name << \"年龄:\" << s1.age << \"分数：\" << s1.score << endl;\n", "\n", " //2.2 struct Student s2 = { ... }\n", " struct Student s2 = { \"李四\",19,80 };\n", " cout << \"姓名：\" << s2.name << \"年龄:\" << s2.age << \"分数：\" << s2.score << endl;\n", " \n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "运行结果： \n", " - 姓名：张三年龄:18分数：100 \n", " - 姓名：李四年龄:19分数：80 \n", " - 请按任意键继续. . ." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "//自定义数据类型，一些类型的集合组成一个类型\n", "struct Student\n", "{\n", " //成员列表\n", "\n", " //姓名\n", " string name;\n", " //年龄\n", " int age;\n", " //分数\n", " int score;\n", "}s3; //2.3 创建结构体的时候，顺便创建个结构体变量\n", "\n", "int main()\n", "{\n", " //2.3 \n", " s3.name = \"王五\";\n", " s3.age = 20;\n", " s3.score = 60;\n", "\n", " cout << \"姓名：\" << s3.name << \"年龄:\" << s3.age << \"分数：\" << s3.score << endl;\n", "\n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "运行结果： \n", " - 姓名：王五年龄:20分数：60 \n", " - 请按任意键继续. . ." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 1.1 结构体定义和使用" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "① 作用：将自定义的结构体放入到数组中方便维护。\n", "\n", "② 语法：struct 结构体名 数组名[元素个数] = { {},{},...,{} }" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "//自定义数据类型，一些类型的集合组成一个类型\n", "struct Student\n", "{\n", " //成员列表\n", "\n", " //姓名\n", " string name;\n", " //年龄\n", " int age;\n", " //分数\n", " int score;\n", "}; \n", "\n", "int main()\n", "{\n", " //2、创建结构体数组\n", " struct Student stuArray[3] =\n", " {\n", " {\"张三\",18,100},\n", " {\"李四\",28,99},\n", " {\"王五\",38,66}\n", " };\n", "\n", " //3、给结构体数组中的元素赋值\n", " stuArray[2].name = \"赵六\";\n", " stuArray[2].age = 80;\n", " stuArray[2].score = 60;\n", "\n", " //4、遍历结构体数组\n", " for (int i = 0; i < 3; i++)\n", " {\n", " cout << \"姓名：\" << stuArray[i].name << \"年龄：\" << stuArray[i].age << \"分数：\" << stuArray[i].score << endl;\n", " }\n", "\n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "运行结果： \n", " - 姓名：张三年龄：18分数：100 \n", " - 姓名：李四年龄：28分数：99 \n", " - 姓名：赵六年龄：80分数：60\n", " - 请按任意键继续. . ." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 1.2 结构体数组" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "① 作用：将自定义的结构体放入到数组中方便维护。\n", "\n", "② 语法：struct 结构体名 数组名[元素个数] = { {},{},...,{} }" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "//自定义数据类型，一些类型的集合组成一个类型\n", "struct Student\n", "{\n", " //成员列表\n", "\n", " //姓名\n", " string name;\n", " //年龄\n", " int age;\n", " //分数\n", " int score;\n", "};\n", "\n", "int main()\n", "{\n", " //2、创建结构体数组\n", " struct Student stuArray[3] =\n", " {\n", " {\"张三\",18,100},\n", " {\"李四\",28,99},\n", " {\"王五\",38,66}\n", " };\n", "\n", " //3、给结构体数组中的元素赋值\n", " stuArray[2].name = \"赵六\";\n", " stuArray[2].age = 80;\n", " stuArray[2].score = 60;\n", "\n", " //4、遍历结构体数组\n", " for (int i = 0; i < 3; i++)\n", " {\n", " cout << \"姓名：\" << stuArray[i].name << \"年龄：\" << stuArray[i].age << \"分数：\" << stuArray[i].score << endl;\n", " }\n", "\n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "运行结果： \n", " - 姓名：张三年龄：18分数：100 \n", " - 姓名：李四年龄：28分数：99 \n", " - 姓名：赵六年龄：80分数：60 \n", " - 请按任意键继续. . ." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 1.3 结构体指针" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "① 作用：通过指针访问结构体中的成员。\n", "\n", "② 利用操作符 · > 可以通过结构体指针访问结构体属性。" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "\n", "//结构体指针\n", "\n", "//定义学生结构体\n", "struct Student\n", "{\n", " string name; //姓名\n", " int age; //年龄\n", " int score; //分数\n", "};\n", "\n", "int main()\n", "{\n", " // 1、创建学生结构体变量，这里的 struct 可以省略\n", " struct Student s = { \"张三\",18,100 };\n", "\n", " //2、通过指针指向结构体变量\n", " struct Student* p = &s; //对s取地址， tudent * p 类似 int * p，这里的 struct 可以省略\n", "\n", " //3、通过指针访问结构体变量中的数据\n", " //通过结构体指针 访问结构体中的属性，需要利用'->'\n", " cout << \"姓名：\" << p->name << \"年龄：\" << p->age << \"分数：\" << p->score << endl;\n", "\n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "运行结果： \n", "- 姓名：张三年龄：18分数：100 \n", "- 请按任意键继续. . ." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 1.4 结构体嵌套结构体" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "① 结构体中的成员可以是另一个结构体。" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "\n", "//因为老师的结构体里有学生的结构体，所以学生结构体要在老师结构体前面先定义\n", "//定义学生结构体\n", "struct student\n", "{\n", " string name; //姓名\n", " int age; //年龄\n", " int score; //分数\n", "}; \n", "\n", "//定义老师结构体\n", "struct teacher\n", "{\n", " int id; //教师编号\n", " string name; //教师姓名\n", " int age; //年龄\n", " struct student stu; //学生结构体\n", "};\n", "\n", "int main()\n", "{\n", " //结构体嵌套结构体\n", " //创建老师\n", " teacher t;\n", " t.id = 10000;\n", " t.name = \"老王\";\n", " t.age = 50;\n", " t.stu.name = \"小王\";\n", " t.stu.age = 20;\n", " t.stu.score = 60;\n", "\n", " cout << \"老师姓名：\" << t.name << \"老师编号：\" << t.id << \"老师年龄：\" << t.age\n", " << \"老师辅导的学生姓名：\" << t.stu.name << \"学生年龄：\" << t.stu.age \n", " << \"学生考试分数：\" << t.stu.score << endl;\n", "\n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "运行结果： \n", " - 老师姓名：老王 老师编号：10000 老师年龄：50 老师辅导的学生姓名：小王 学生年龄：20 学生考试分数：60\n", " - 请按任意键继续. . ." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 1.5 结构体做函数参数" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "① 作用：将结构体作为参数向函数中传递，传递方式有两种。\n", "\n", "② 传递方式有两种：\n", "\n", "1. 值传递\n", "2. 地址传递" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "\n", "//定义学生结构体\n", "struct student\n", "{\n", " string name; //姓名\n", " int age; //年龄\n", " int score; //分数\n", "};\n", "\n", "//定义老师结构体\n", "struct teacher\n", "{\n", " int id; //教师编号\n", " string name; //教师姓名\n", " int age; //年龄\n", " struct student stu; //学生结构体\n", "};\n", "\n", "//打印学生信息的函数\n", "//1、值传递\n", "void printStudent1(struct student s)\n", "{\n", " cout << \"子函数 值传递前 姓名：\" << s.name << \"年龄：\" << s.age << \"分数：\" << s.score << endl;\n", "\n", " s.age = 100;\n", "}\n", "\n", "//2、地址传递\n", "void printStudent2(struct student* p)\n", "{\n", " cout << \"子函数 地址传递前 姓名：\" << p->name << \"年龄：\" << p->age << \"分数：\" << p->score << endl;\n", "\n", " p->score = 90;\n", "}\n", "\n", "int main()\n", "{\n", " //结构体做函数参数\n", " //将学生传入到一个参数中，打印学生身上的所有信息\n", "\n", " //创建结构体变量\n", " struct student s;\n", " s.name = \"张三\";\n", " s.age = 20;\n", " s.score = 85;\n", "\n", " cout << \"main函数 传递前 姓名：\" << s.name << \"年龄：\" << s.age << \"分数：\" << s.score << endl;\n", "\n", " printStudent1(s);\n", "\n", " cout << \"子函数 值传递后 姓名：\" << s.name << \"年龄：\" << s.age << \"分数：\" << s.score << endl;\n", "\n", " printStudent2(&s);\n", "\n", " cout << \"子函数 地址传递后 姓名：\" << s.name << \"年龄：\" << s.age << \"分数：\" << s.score << endl;\n", "\n", "\n", " cout << \"main函数 传递后 姓名：\" << s.name << \"年龄：\" << s.age << \"分数：\" << s.score << endl;\n", "\n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "运行结果： \n", " - main函数 传递前 姓名：张三年龄：20分数：85 \n", " - 子函数 值传递前 姓名：张三年龄：20分数：85 \n", " - 子函数 值传递后 姓名：张三年龄：20分数：85 \n", " - 子函数 地址传递前 姓名：张三年龄：20分数：85 \n", " - 子函数 地址传递后 姓名：张三年龄：20分数：90 \n", " - main函数 传递后 姓名：张三年龄：20分数：90 \n", " - 请按任意键继续. . ." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 1.6 结构体中const使用" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "① 作用：const来防止误操作。" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "\n", "//const 的使用场景\n", "\n", "struct student\n", "{\n", " //姓名\n", " string name;\n", " //年龄\n", " int age;\n", " //分数\n", " int score;\n", "};\n", "\n", "//将函数中形参设置为指针，用地址传递，而不是值传递，可以减少内存空间，而且不会复制新的副本\n", "//值传递需要复制新的副本，如果有成千上万个学生调用结构体，会复制成千上个副本\n", "void printStudents(const student* s)\n", "{\n", " s->age = 150; //报错，因为假如const之后，一旦有修改的操作就会报错，可以防止我们的误操作。\n", " cout << \"姓名：\" << s->name << \"年龄：\" << s->age << \"分数：\" << s->score << endl;\n", "}\n", "\n", "\n", "int main()\n", "{\n", " //创建结构体变量\n", " struct student s = { \"张三\",15,70 };\n", "\n", " //通过函数打印结构体变量信息\n", " printStudents(&s);\n", "\n", " cout << \"main中张三年龄为：\" << s.age << endl;\n", "\n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 1.7 结构体案例(一)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "案例描述：学校正在做毕设项目，每名老师带领5个学生，总共有3名老师，需求如下：设计学生和老师的结构体，其中在老师的结构体中，有老师姓名和一个存放5名学生的数组作为成员，学生的成员有姓名、考试分数、创建数组存放3名老师，通过函数给每个老师及所带的学生赋值。最终打印出老师数据以及老师所带的学生数据。" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "#include \n", "using namespace std;\n", "#include \n", "#include \n", "\n", "//学生结构体定义\n", "struct Student\n", "{\n", " //姓名\n", " string sName;\n", " //学生数组\n", " int score;\n", "};\n", "\n", "//老师结构体\n", "struct Teacher\n", "{\n", " //姓名\n", " string tName;\n", " //学生数组\n", " struct Student sArray[5];\n", "};\n", "\n", "//给老师和学生赋值的函数\n", "void allocateSpace(struct Teacher tArray[], int len) //接收数组的两种方式：一用指针，二用数组名 struct Teacher tArray[]\n", "{\n", " string nameSeed = \"ABCDE\";\n", " //给老师开始赋值\n", " for (int i = 0; i < len; i++)\n", " {\n", " tArray[i].tName = \"Teacher_\";\n", " tArray[i].tName += nameSeed[i];\n", "\n", " //通过循环给每名老师所带的学生赋值\n", " for (int j = 0; j < 5; j++)\n", " {\n", " tArray[i].sArray[j].sName = \"Student_\";\n", " tArray[i].sArray[j].sName += nameSeed[j];\n", "\n", " int random = rand() % 61 + 40; // 40 ~ 100\n", " tArray[i].sArray[j].score = random; //\n", "\n", " }\n", " }\n", "}\n", "\n", "//打印所有信息\n", "void printInfo(struct Teacher tArray[], int len)\n", "{\n", " for (int i = 0;i\n", "using namespace std;\n", "\n", "//1、设计英雄结构体\n", "struct Hero\n", "{\n", " //姓名\n", " string name;\n", " //年龄\n", " int age;\n", " //性别\n", " string sex;\n", "};\n", "\n", "//冒泡排序，实现年龄升序排列\n", "void bubbleSort(struct Hero heroArray[], int len)\n", "{\n", " for (int i = 0; i < len - 1; i++)\n", " {\n", " for (int j = 0; j < len - i - 1; j++)\n", " {\n", " //如果j下标的年龄大于j+1下标的元素的年龄，交换两个元素\n", " if (heroArray[j].age > heroArray[j + 1].age)\n", " {\n", " struct Hero temp = heroArray[j]; //创建一个临时结构体变量\n", " heroArray[j] = heroArray[j + 1];\n", " heroArray[j + 1] = temp;\n", " }\n", " }\n", " }\n", "}\n", "\n", "void printHero(struct Hero heroArray[], int len)\n", "{\n", " for (int i = 0; i < len; i++)\n", " {\n", " cout << \"姓名：\" << heroArray[i].name << \" 年龄：\" << heroArray[i].age\n", " << \" 性别：\" << heroArray[i].sex << endl;\n", " }\n", "}\n", "\n", "int main()\n", "{\n", "\n", " //2、创建数组存放5名英雄\n", " struct Hero heroArray[5] =\n", " {\n", " {\"刘备\",23,\"男\"},\n", " {\"关羽\",22,\"男\"},\n", " {\"张飞\",20,\"男\"},\n", " {\"赵云\",21,\"女\"},\n", " {\"貂蝉\",19,\"女\"},\n", " };\n", "\n", " int len = sizeof(heroArray) / sizeof(heroArray[0]);\n", " cout << \"排序前的打印结果\" << endl;\n", " for (int i = 0; i < len; i++)\n", " {\n", " cout << \"姓名：\" << heroArray[i].name << \" 年龄：\" << heroArray[i].age\n", " << \" 性别：\" << heroArray[i].sex << endl;\n", " }\n", "\n", " //3、对数组进行排序，按照年龄进行升序排序\n", " bubbleSort(heroArray, len);\n", "\n", " //4、将排序后结果打印输出\n", " cout << \"排序后的打印结果\" << endl;\n", " printHero(heroArray,len);\n", "\n", "\n", " system(\"pause\");\n", "\n", " return 0;\n", "\n", "}" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "运行结果： \n", " - 排序前的打印结果 \n", " - 姓名：刘备 年龄：23 性别：男 \n", " - 姓名：关羽 年龄：22 性别：男 \n", " - 姓名：张飞 年龄：20 性别：男 \n", " - 姓名：赵云 年龄：21 性别：女 \n", " - 姓名：貂蝉 年龄：19 性别：女 \n", " - 排序后的打印结果 \n", " - 姓名：貂蝉 年龄：19 性别：女 \n", " - 姓名：张飞 年龄：20 性别：男 \n", " - 姓名：赵云 年龄：21 性别：女 \n", " - 姓名：关羽 年龄：22 性别：男 \n", " - 姓名：刘备 年龄：23 性别：男 \n", " - 请按任意键继续. . ." ] } ], "metadata": { "kernelspec": { "display_name": "Python 3.6.3", "language": "python", "name": "python3.6.3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.6.3" }, "toc": { "base_numbering": 1, "nav_menu": {}, "number_sections": false, "sideBar": true, "skip_h1_title": false, "title_cell": "Table of Contents", "title_sidebar": "Contents", "toc_cell": false, "toc_position": {}, "toc_section_display": true, "toc_window_display": true } }, "nbformat": 4, "nbformat_minor": 4 }