链栈

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

#define false 0
#define true 1

typedef int ElementType;
typedef int bool;
typedef struct SNode *PtrToSNode;
struct SNode
{
    ElementType Data;
    PtrToSNode Next;
};
typedef PtrToSNode Stack;

Stack CreateStack();       //链栈的构建
bool IsEmpty(Stack S);    //判断栈是否为空
void Push(Stack S, ElementType X);    //入栈
ElementType Pop(Stack S);     //出栈


Stack CreateStack()       //链栈的构建
{
    Stack S;

    S = malloc(sizeof(struct SNode));
    S->Next = NULL;
    return S;
}

bool IsEmpty(Stack S)    //判断栈是否为空
{
    return (S->Next == NULL);
}

void Push(Stack S, ElementType X)    //入栈
{
    PtrToSNode TmpCell;

    TmpCell = (PtrToSNode)malloc(sizeof(struct SNode));
    TmpCell->Data = X;
    TmpCell->Next = S->Next;
    S->Next = TmpCell;
}

ElementType Pop(Stack S)     //出栈
{
    if(IsEmpty(S))
    {
        printf("栈为空,出栈失败！
");
        return false;
    }

    PtrToSNode FirstCell;
    ElementType TopElem;

    FirstCell = S->Next;
    TopElem = FirstCell->Data;
    S->Next = FirstCell->Next;
    free(FirstCell);
    return TopElem;
}