作业 - 动态数组

main.m

#import <Foundation/Foundation.h>
#include "Array.h"
#include "Object.h"
#include "Student.h"

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        
        Array *arr = ArrayCreate();
        Anypointer student;
        
        student = (Object*)StudentNew("小明", 20);
        ArrayAdd(arr, student);
        OBJECT_RELEASE(student);
        
        student = (Object*)StudentNew("大明", 21);
        ArrayAdd(arr, student);
        OBJECT_RELEASE(student);
        
        student = (Object*)StudentNew("小李", 22);
        ArrayAdd(arr, student);
        OBJECT_RELEASE(student);
        
        student = (Object*)StudentNew("小张", 24);
        ArrayAdd(arr, student);
        OBJECT_RELEASE(student);
        
        student = (Object*)StudentNew("小马", 28);
        ArrayAdd(arr, student);
        OBJECT_RELEASE(student);
        
        student = (Object*)StudentNew("小陈", 29);
        ArrayAdd(arr, student);
        OBJECT_RELEASE(student);
        
        student = (Object*)StudentNew("小蔡", 25);
        ArrayAdd(arr, student);
        OBJECT_RELEASE(student);
        
        student = (Object*)StudentNew("小王", 26);
        ArrayAdd(arr, student);
        OBJECT_RELEASE(student);
        
        printlist(arr);
        
        printf("删除小李\n");
        
        ArrayRemoveAt(arr, 2);
        
        printlist(arr);
        
        printf("加入老王\n");
        student = (Object*)StudentNew("老王", 50);
        ArrayInsertAt(arr, student, 6);
        
        printlist(arr);
        
        ArrayDestory(arr);
    }
    return 0;
}

Array.h

#ifndef Array_h
#define Array_h

#include "Object.h"
#include <stdio.h>

typedef Object* Anypointer;

typedef struct Array_ {
           int retainCount_;
           int length_;        //实际长度
           int capacity_;      //分配的内存长度
    Anypointer *students_;     //数组类型
}Array;

Array *ArrayCreate();          //创建数组

int ArrayGetLength(Array *arr); //获取长度

void ArrayAdd(Array *arr, Anypointer student); //添加元素

void ArrayInsertAt(Array* arr, Anypointer student, int index);//插入元素

void ArrayRemoveAt(Array *arr, int index);//删除元素

Anypointer ArrayGetAt(Array *arr, int index);//获取指定元素

void printlist(Array *arr);//打印数组

void ArrayDestory(Array *arr); //数组销毁

#endif /* Array_h */

Array.c

#include "Array.h"
#include "Object.h"
#include "Student.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>


static Anypointer *allocMemoryByCapacity(Array *arr){
    return malloc(sizeof(Anypointer) * arr->capacity_);
}

Array *ArrayCreate(){                                   //创建数组
    Array *arr       = malloc(sizeof(Array));
    arr -> length_   = 0;
    arr -> capacity_ = 10;
    arr -> students_ = allocMemoryByCapacity(arr);
    return arr;
}

int ArrayGetLength(Array *arr){                         //获取实际长度
    return arr->length_;
}

void ArrayAdd(Array *arr, Anypointer student){          //添加元素
    if (arr->length_ >= arr->capacity_) {
        arr->capacity_ *= 2;
        Anypointer *oldValue = arr->students_;
        arr->students_ = allocMemoryByCapacity(arr);
        memcpy(arr->students_, oldValue, arr->length_);
        free(oldValue);
    }
    arr->students_[arr->length_] = student;
    OBJECT_RETAIN(student);
    arr->length_ ++;
}

void ArrayInsertAt(Array* arr, Anypointer student, int index){ //插入元素
    ArrayAdd(arr, student);
    for (int i = arr->length_ - 1; i >= index; i --) {
        arr->students_[i] = arr->students_[i-1];
    }
    arr->students_[index - 1] = student;
    OBJECT_RETAIN(student);
}

void ArrayRemoveAt(Array *arr, int index){      //删除元素
    assert(index >= 0 && index < arr->length_);
    OBJECT_RELEASE(ArrayGetAt(arr, index));
    arr->length_ --;
    for (int i = index; i < arr->length_; i++) {
        arr->students_[i] = arr->students_[i+1];
    }
}

Anypointer ArrayGetAt(Array *arr, int index){   //获取元素
    assert(index >= 0 && index <= arr->length_);
    return arr->students_[index];
}

void printlist(Array *arr){                     //打印数组
    for (int i = 0; i < arr->length_; i++) {
        printf("位置:%2d ", i+1);
        printf("名字:%s ", StudentGetName((Student*)arr->students_[i]));
        printf("年龄:%d \n", StudentGetAge((Student*)arr->students_[i]));
    }
}

void ArrayDestory(Array *arr){ //数组销毁
    free(arr->students_);
    free(arr);
    printf("arr released.\n");
}

Object.h

#ifndef Object_h
#define Object_h
#include <stdio.h>

//引用计数法 管理内存

typedef struct Object_{
           int retainCount_;
}Object;

#define OBJECT_RETAIN(obj)       ObjectRetain((Object*)obj)
#define OBJECT_RELEASE(obj)      ObjectRelease((Object*)obj)
#define OBJECT_RETAIN_COUNT(obj) ObjectRetainCount((Object*)obj)

void ObjectRetain(Object *obj);

void ObjectRelease(Object *obj);

int  ObjectRetainCount(Object *obj);

#endif /* Object_h */

Object.c

#include "Object.h"
#include <stdlib.h>

void ObjectRetain(Object *obj){         //引用计数++
     obj->retainCount_ ++;
}

void ObjectRelease(Object *obj){        //引用计数--
    obj->retainCount_ --;
    if (obj->retainCount_ <= 0) {
        free(obj);
        printf("Released the obj.\n");
    }
}

int ObjectRetainCount(Object *obj){     //获取引用计数
    return obj->retainCount_;
}

Student.h

#ifndef Student_h
#define Student_h

#include <stdio.h>
#include <stdlib.h>
#include "Object.h"

typedef struct Student_{        //创建 Student 结构体
           int retainCount_;
          char *name_;
           int age_;
}Student;

Student *StudentNew(char *name, int age);  //新建 Student

   char *StudentGetName(Student* student); //获取姓名

    int StudentGetAge(Student* student);   //获取年龄

#endif /* Student_h */

Student.c

#include "Student.h"

Student* StudentNew(char *name, int age){       //新建 Student
    Student *student = malloc(sizeof(Student));
    OBJECT_RETAIN(student);
    student->name_   = name;
    student->age_    = age;
    return student;
}

char* StudentGetName(Student* student){         //获取姓名
    return student->name_;
}

int StudentGetAge(Student* student){            //获取年龄
    return student->age_;
}