数据结构 动态数组

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define FAILURE -1
#define SUCCESS 0


typedef struct{
   int  *array_ptr;     //数组指针
   int  size;           //元素个数
   int  capacity;       //容量大小
}Array_def;


//初始化
Array_def* array_init()
{
    Array_def *arr = (Array_def*)malloc(sizeof(Array_def));
    if (arr == NULL)
    {
        printf("malloc error\n");
        return NULL;
    }
 
    arr->size = 0;
    arr->capacity = 5;
    arr->array_ptr = (int*)malloc(sizeof(int)*arr->capacity);
    return arr;
}

//尾插入数据到数组中
int array_push_back(Array_def* arr, int value)
{
    if (arr == NULL)
    {
        printf("param is null\n");
        return FAILURE;
    }

    //元素个数等于容量大小需重新申请新的空间
    if (arr->size == arr->capacity)
    {
        int *newspace_ptr = (int*)malloc(sizeof(int)*arr->capacity*2);
        
        if (newspace_ptr == NULL)
        {
            printf("malloc error\n");
            return FAILURE;
        }
        
        memset(newspace_ptr, 0x00, sizeof(sizeof(int)*arr->capacity*2));
        memcpy(newspace_ptr, arr->array_ptr, sizeof(int)*arr->capacity);
        free(arr->array_ptr);
        
        arr->array_ptr = newspace_ptr;
        arr->capacity = arr->capacity * 2;
    }
    
    arr->size++;
    arr->array_ptr[arr->size-1] = value;
    
    return 0;
}

//根据值删除数组中元素
int array_pop_byvalue(Array_def* arr, int value)
{
    int pos = 0;
    if (arr == NULL)
    {
        printf("param is null\n");
        return FAILURE;
    }
    for (int i=0; i<arr->size; i++)
    {
        if (arr->array_ptr[i] == value)
        {
            pos = i;
            break;
        }
    }
    for (int i=pos; i<arr->size; i++)
    {
        arr->array_ptr[i] = arr->array_ptr[i+1];
    }
    arr->size--;
    return pos;
}

//根据索引下标删除数组中元素
int array_pop_bypos(Array_def* arr, int pos)
{
    if (arr == NULL)
    {
        printf("param is null\n");
        return FAILURE;
    }
    for (int i=pos; i<arr->size; i++)
    {
        arr->array_ptr[i] = arr->array_ptr[i+1];
    }
    arr->size--;
    return 0;
}

//输出元素
int  array_print(Array_def* arr)
{
    if (arr == NULL)
    {
        printf("param is null\n");
        return FAILURE;
    }
    for (int i=0; i<arr->size; i++)
    {
        printf("%d ", arr->array_ptr[i]);
    }
    printf("\n");
}

//数组元素个数
int array_size(Array_def* arr)
{
    return arr->size;
}

//数组容量
int array_capacity(Array_def* arr)
{
    return arr->capacity;
}

void test1()
{
    Array_def* arr = array_init();
    for (int i=0; i<20; i++)
    {
        array_push_back(arr, i);
    }
    array_print(arr);
    
    array_pop_byvalue(arr, 17);
    array_print(arr);
    
    array_pop_bypos(arr, 2);
    array_print(arr);

}
int main()
{
    test1();
    return 0;
}