顺序字母栈的实现

代码很简单，但怎么着学习也得一步一步来

#include "stack.h"
Status InitStack(SqStack *s)
{
        s->base=(SElemType *)malloc(STACK_INIT_SIZE*sizeof(SElemType));
        if(!s)
        {
                return MALLOC_ERROR;
        }
        s->top=s->base;
        s->stacksize=STACK_INIT_SIZE;
        return OK;
}

Status DestroyStack(SqStack *s)
{
        if(!s)
        {
                return ERROR;
        }
        free(s->base);
        s->base=NULL;
        s->stacksize=0;
        return OK;
}
Status ClearStack(SqStack *s)
{
        if(!s||!s->base)
        {
                return ERROR;
        }
        memset(s->base,0,s->stacksize*sizeof(SElemType));
        s->top=s->base;
        return OK;
}
Status ShowStack(SqStack *s)
{
        if(!s)
        {
                return ERROR;
        }
        if(s->top==s->base)
        {
                printf("Can't Show,since Stack is Empty!\n");
                return ERROR;
        }
        SElemType *p=NULL;
        int num=s->top-s->base;
        for(p=s->base;p<s->top;p++)
        {
                printf("[%d/%d][%c]\t",p-s->base+1,s->top-s->base,*p);
        }
        printf("\n");
        return OK;

}
Status StackEmpty(SqStack *s)
{
        if(!s)
        {
                return ERROR;
        }
        if(s->base==s->top)
        {
                return OK;
        }
}
int StackLength(SqStack *s)
{
        return (s->top - s->base)/sizeof(SElemType);
}
Status GetTop(SqStack *s,SElemType* e)
{
        if(!s)
        {
                return ERROR;
        }
        *e=*--(s->top);
        return OK;
}//Don't Return Local_Var Of The Function,Else The Result Is Not Defined!

Status Push(SqStack *s,SElemType e)
{
        if(!s||!s->top)
        {
                return ERROR;
        }
        if(s->top - s->base ==STACK_INIT_SIZE-1)
        {
                printf("Need Realloc!\n");
                return ERROR;//Temporary,no deal with it!

        }
        *(s->top)=e;
        s->top++;
        return OK;
}
Status Pop(SqStack *s,SElemType* e)
{
        if(!s)
        {
                return ERROR;
        }
        if(s->top==s->base)
        {
                printf("Can't pop,since Stack is Empty!\n");
                return ERROR;
        }
        *e=*(s->top--);
        return OK;
}
        int
main(void)
{
        SqStack Stack ,*pStack=&Stack;
        SElemType e;
        SElemType d;
        if(InitStack(pStack)==OK)
        {
                printf("Init Stack Ok!\n");
        }
        if(StackEmpty(pStack)==OK)
        {
                printf("Empty Stack!\n");
        }
        printf("stack_len:[%d]\n",StackLength(pStack));
        if(Push(pStack,'A')==OK)
        {
                printf("Push Ok!\n");
                printf("stack_len:[%d]\n",StackLength(pStack));
        }
        Push(pStack,'B');
        Push(pStack,'C');
        Push(pStack,'D');
        ShowStack(pStack);
        Pop(pStack,&d);
        ShowStack(pStack);
        Pop(pStack,&d);
        ShowStack(pStack);
        Push(pStack,'E');
        ShowStack(pStack);
        Pop(pStack,&d);
        ShowStack(pStack);
        if(OK==GetTop(pStack,&e))
        {
                printf("TopElem:[%c]\n",e);
        }
        if(DestroyStack(pStack)==OK)
        {
                printf("Destroy Stack Ok!\n");
        }
        return 0;
}


头文件：


#ifndef _STACK_H
#define _STACK_H
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define STACK_INIT_SIZE 100
#define STACK_INCREMENT 10
#define OK 0
#define ERROR -1
#define ARG_ERROR -2
#define MALLOC_ERROR -3

typedef int Status;
typedef char SElemType;

typedef struct SqStack
{
                SElemType *base;
                SElemType *top;
                int stacksize;//Max capacity of stack

}SqStack;

#endif