顺序表的扩容

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

#define ERROR 0
#define OK 1

typedef struct Vector {
    int size, length;
    int *data;
} Vector;

void init(Vector *vector, int size) {
    vector->size = size;
    vector->length = 0;
    vector->data = (int *)malloc(sizeof(int) * size);
}

// 实现扩容函数 expand
void expand(Vector *vector){
    int *old_data=vector->data;
    //将容量 vector->size更新为原来的2倍
    vector->size=vector->size * 2;
    //让vector->data指向它的首地址
    vector->data =(int *)malloc(sizeof(int) * vector->size);

    for(int i=0;i<vector->length;++i){
      vector->data[i]= old_data[i];
    }
   //把旧空间回收
    free(old_data); 
}

int insert(Vector *vector, int loc, int value) {
    if (loc < 0 || loc > vector->length) {
        return ERROR;
    }
    if (vector->length >= vector->size) {
        //return ERROR;
        //扩容
        expand(vector);
    }
    for (int i = vector->length; i > loc; --i) {
        vector->data[i] = vector->data[i - 1];
    }
    vector->data[loc] = value;
    vector->length++;
    return OK;
}

void clear(Vector *vector) {
    free(vector->data);
    free(vector);
}

int main() {
    Vector *a = (Vector *)malloc(sizeof(Vector));
    init(a, 100);
    printf("%d\n", insert(a, 1, 0));
    printf("%d\n", insert(a, 0, 1));
    printf("%d\n", insert(a, 2, 1));
    printf("%d\n", insert(a, 1, 2));
    printf("%d\n", insert(a, 0, 3));
    clear(a);
    return 0;
}