栈的链表实现

#include <stdio.h>
#include <stdlib.h>
typedef int datatype;
typedef struct stack_linked
{
    int data;
    struct stack_linked * next;
}slinked,*slinked_p;
slinked_p stack_creat();
int stack_push(slinked_p S,datatype value);
int stack_empty(slinked_p S);
datatype stack_pop(slinked_p S);
int stack_pop1(slinked_p S,datatype *value);
int stack_top(slinked_p S);
void stack_clear(slinked_p S);
void stack_clear(slinked_p S);
void stack_free(slinked_p S);
int main(int argc, const char *argv[])
{
    int value;
    slinked_p S = stack_creat();
    if(NULL == S)
    {
        printf("函数调用失败\n");
        return -1;
    }
    stack_push(S,1);
    stack_push(S,2);
    stack_push(S,3);
    stack_push(S,4);
    //printf("top = %d\n",stack_pop(S));
    stack_pop1(S,&value);
    printf("pop = %d\n",value);
    printf("top = %d\n",stack_top(S));
    stack_clear(S);
    stack_free(S);
    return 0;
}

slinked_p stack_creat()
{
    slinked_p S = (slinked_p)malloc(sizeof(slinked));
    if(S == NULL)
    {
        printf("空间开辟失败\n");
        return NULL;
    }
    S->next = NULL;
    return S;
}

int stack_push(slinked_p S,datatype value)
{
    slinked_p p = (slinked_p)malloc(sizeof(slinked));
    if(NULL == p)
    {
        printf("内存空间开辟失败\n");
        return -1;
    }
    p->next = S->next;
    S->next = p;
    p->data = value;
    return 0;
}

datatype stack_pop(slinked_p S)
{
    if(stack_empty(S))
    {
        printf("栈空间为空\n");
        return -1;
    }
    slinked_p p = S->next;
    int value = p->data;
    S->next = p->next;
    free(p);
    p = NULL;
    return value;
}
int stack_empty(slinked_p S)
{
    return S->next == NULL?1:0;
}

int stack_pop1(slinked_p S,datatype *value)
{
    if(stack_empty(S))
    {
        printf("栈空间为空\n");
        return -1;
    }
    slinked_p p = S->next;
    *value = p->data;
    S->next = p->next;
    free(p);
    p = NULL;
    return 0;
}
//取栈顶元素
int stack_top(slinked_p S)
{
    return S->next->data;
}

//清空栈
void stack_clear(slinked_p S)
{
    while(!stack_empty(S))
    {
        printf("%d ",stack_pop(S));
    }
    putchar(10);
}

//free栈

void stack_free(slinked_p S)
{
    stack_clear(S);
    free(S);
    S = NULL;
}