package demo;
import java.util.Arrays;
public class DiyArrayListDemo {
  public static void main(String[] args){
    int[] arr = {5,8,10};
    System.out.println(Arrays.toString(arr));//=>[5, 8, 10]
    arr = DiyArrayList.add(arr, 15);
    arr = DiyArrayList.add(arr, 20);
    arr = DiyArrayList.add(arr, 25);
    System.out.println(Arrays.toString(arr)); //=>[5, 8, 10, 15, 20, 25]
    arr = DiyArrayList.remove(arr, 1);
    System.out.println(Arrays.toString(arr)); //=>[5, 10, 15, 20, 25]
  }
}
class DiyArrayList{
  public static int[] add(int[] src,Integer newData){
    //定義目標(biāo)數(shù)組，長度是比原始數(shù)組多一位
    int[] dest = new int[src.length+1];
    //從src的0位開始，復(fù)制到dest的0位置，復(fù)制長度是src的長度
    System.arraycopy(src, 0, dest, 0, src.length);
    //填充最后一位的值
    dest[src.length] = newData;
    return dest;
  }
  public static int[] remove(int[] src,Integer index){
    //定義目標(biāo)數(shù)組，長度是比原始數(shù)組少一位
    int[] desc = new int[src.length-1];
    for(int i=0; i<src.length; i++){
      //超過索引index的數(shù)據(jù)往前移動一位
      if(i > index){
        desc[i-1] = src[i];
      }else{
        desc[i] = src[i];
      }
    }
    return desc;
  }
}

//定義一個結(jié)構(gòu)體，data里面儲存的是int類型指數(shù)組，count存儲的是數(shù)組的長度
typedef struct arrayList {
  int* data;
  int count;
} ArrayList;
void initArrayList(ArrayList* list);
void arrayListAdd(ArrayList* list, int data);
void arrayListRemove(ArrayList* list, int index);
void printAll(ArrayList list);
demo.c
#include <stdio.h>
#include <stdlib.h>
#include "test.h"
int main() {
  ArrayList arrayList;
  initArrayList(&arrayList);
  arrayListAdd(&arrayList, 10);
  arrayListAdd(&arrayList, 13);
  arrayListAdd(&arrayList, 15);
  arrayListRemove(&arrayList, 2);
  printAll(arrayList);
}
/********************************
函數(shù)名:initArrayList()
功能：初始化ArrayList結(jié)構(gòu)體
輸入：ArrayList類型結(jié)構(gòu)體指針
輸出：無
*/
void initArrayList(ArrayList* arrayList) {
  arrayList->data = NULL;
  arrayList->count = 0;
}
/*******************************
函數(shù)名:arrayListAdd()
功能：添加數(shù)據(jù)到ArrayList類型結(jié)構(gòu)體里面的數(shù)組
輸入：ArrayList類型結(jié)構(gòu)體指針，int類型數(shù)據(jù)
輸出：無
*/
void arrayListAdd(ArrayList* list, int data) {
  int count = list->count;
  //重新申請空間，空間比現(xiàn)在的長度大1個int長度
  int* newDataArr = (int*)realloc(list->data,sizeof(int) * (++count));
  if (newDataArr != NULL) {
    list->data = newDataArr;
    list->data[count - 1] = data;
    list->count++;
  }
  else {
    puts("申請空間失敗");
  }
}
/*******************************
函數(shù)名：arrayListRemove()
功能：根據(jù)index刪除ArrayList類型結(jié)構(gòu)體里面的數(shù)組元素
輸入：ArrayList類型結(jié)構(gòu)體指針，int類型索引
輸出：無
*/
void arrayListRemove(ArrayList* list, int index) {
  if (index > list->count) {
    puts("超出數(shù)組索引");
    exit(1);
  }
  //把大于index的數(shù)組數(shù)據(jù)往前移動一個索引
  for (int i = 0; i < list->count; i++) {
    if (i > index) {
      list->data[i - 1] = list->data[i];
    }
  }
  int count = list->count;
  //重新申請空間，數(shù)組長度縮減一個int長度
  int *newDataArr = realloc(list->data, sizeof(int) * (--count));
  if (newDataArr != NULL) {
    list->data = newDataArr;
    list->count = count;
  }
  else {
    puts("申請空間失敗");
  }
}
/********************************
函數(shù)名：打印所有數(shù)組
輸入：ArrayList類型結(jié)構(gòu)體
*/
void printAll(ArrayList list) {
  for (int i = 0; i < list.count; i++) {
    printf("%d \r\n", list.data[i]);
  }
}