数据结构 顺序表 实现增添删减

#include<stdio.h>
#include<malloc.h>
#include<stdlib.h>
typedef int SLDateType;
typedef struct SeqList
{
    SLDateType* a;
    int size;//有效数据个数·
    int capacity;//容量
}SeqList;

void SeqListInit(SeqList* ps)//初始化
{
    ps->a=(SLDateType*)malloc(sizeof(SLDateType)*4);
    if(ps->a==NULL)
    {
        printf("申请内存失败\n");
        exit(-1);//直接结束
    }
    ps->size = 0;
    ps->capacity = 4;
}
void SeqListCheckCapacity(SeqList* ps)//判断是否需要扩容
{
    if(ps->size >= ps->capacity)
    {
        ps->capacity*=2;//扩为原来两倍
        ps->a = (SLDateType*)realloc(ps->a,sizeof(SLDateType)*ps->capacity);
        if(ps->a==NULL)
        {
            printf("申请内存失败\n");
            exit(-1);//直接结束
        }
    }
}
void SeqListPrint(SeqList* ps)//打印
{
    int i;
    for(i=0;i<ps->size;++i)
    {
        printf("%d  ",ps->a[i]);
    }
    printf("\n");
}







void SeqListPushBack(struct SeqList* ps,SLDateType x)//尾加
{
    //得考虑是否满了，满了就得增容
    SeqListCheckCapacity(ps);
    ps->a[ps->size] = x;
    ps->size++;
}
void SeqListPopBack(struct SeqList* ps)//尾删
{
    ps->size--;
}
void SeqListPushFront(struct SeqList* ps,SLDateType x)//头插
{
    int i;
    for(i=ps->size-1;i>=0;i--)
    {
        ps->a[i+1]=ps->a[i];
    }
    ps->a[0]=x;
    ps->size++;
}
void SeqListPopFront(struct SeqList* ps)//头减
{
    int i;
    for(i=1;i<ps->size;i++)
    {
        ps->a[i-1]=ps->a[i];
    }
    ps->size--;
}





void TestSeqList1()
{
    SeqList s;
    SeqListInit(&s);
    SeqListPushBack(&s,1);
    SeqListPushBack(&s,2);
    SeqListPushBack(&s,3);
    SeqListPushBack(&s,4);
    SeqListPushBack(&s,5);
    SeqListPushBack(&s,6);
    SeqListPushBack(&s,7);
    SeqListPushBack(&s,8);
    SeqListPushBack(&s,9);
    SeqListPrint(&s);

    SeqListPopBack(&s);
    SeqListPopBack(&s);
    SeqListPrint(&s);

    SeqListPushFront(&s,0);
    SeqListPushFront(&s,-1);
    SeqListPrint(&s);

    SeqListPopFront(&s);
    SeqListPopFront(&s);
    SeqListPopFront(&s);
    SeqListPrint(&s);
}
int main()
{
    TestSeqList1();
    return 0;
}