链式堆栈

#include<stdio.h>
#include<stdlib.h>
typedef int ElementType;
typedef struct SNode * Pointer;
struct SNode {
ElementType data;
Pointer next;
};
Pointer CreateStack();                //创建堆栈
Pointer Push(ElementType x, Pointer S);       //入栈
int IsEmpty(Pointer S);               //判断是否为空
ElementType Pop(Pointer S);                   //出栈


int main()
{
Pointer head;
head = CreateStack();
int i;
for (i = 0; i < 5; i++)
{
Push(i, head);
}
while (head->next)
{
printf("%d\n", Pop(head));
}
return 0;
}


Pointer CreateStack()
{
Pointer head;
head = (Pointer)malloc(sizeof(struct SNode));
head->next = NULL;
return head;
}


int IsEmpty(Pointer S)
{
if (S->next == NULL) return 1;
else return 0;
}


Pointer Push(int x, Pointer S)
{
Pointer head;
head = (Pointer)malloc(sizeof(struct SNode));
head->data = x;
head->next = S->next;
S->next = head;
return S;
}


ElementType Pop(Pointer S)
{
if (IsEmpty(S))
{
printf("栈为空\n");
return 0;
}
ElementType x;
x = S->next->data;
Pointer P = S->next;
S->next = S->next->next;
free(P);
return x;

}