栈的基本操作

包括构造空栈，销毁栈，把栈置空，检验栈是否为空，求栈的长度，取出栈顶元素，入栈，出栈

#include<stdio.h>#include<stdlib.h>#define STACKMAX 100#define STACKADD 10#define datatype inttypedef struct{    datatype *base;    datatype *top;    int stacksize;}SqStack;int InitStack(SqStack* S);//初始化,成功返回1int Destroy(SqStack* S);//销毁栈,成功返回1int ClearStack(SqStack* S);//把栈置空int StackEmpty(SqStack* S);//若栈为空返回1,否则返回0int StackLenth(SqStack* S);//返回栈的元素个数int GetTop(SqStack* S,datatype* e);//若栈不为空,保存栈顶的元素并返回1;否则返回0int Push(SqStack* S,datatype e);//插入栈顶元素int Pop(SqStack* S,datatype* e);//若栈不为空,则删除栈顶元素并保存返回1,否则返回0int InitStack(SqStack *S){    S->base = (datatype*)malloc(STACKMAX*sizeof(datatype));    S->top = S->base;    S->stacksize = STACKMAX;    return 1;}int Destroy(SqStack* S){    free(S->base);    S->base = NULL;    S->top = NULL;    S->stacksize = 0;    return 1;}int ClearStack(SqStack* S){    S->base = S->top;    return 1;}int StackLenth(SqStack* S){    return S->top - S->base;}int StackEmpty(SqStack* S){    if(S->base == S->top)        return 1;    return 0;}int GetTop(SqStack* S,datatype* e){    if(StackEmpty(S))        return 0;    *e = *(S->top-1);    return 1;}int Push(SqStack* S,datatype e){    if(S->top - S->base >= S->stacksize)    {        S->base = (datatype*)realloc(S->base,(S->stacksize+STACKADD)*sizeof(datatype));        if(!S->base)            return 0;        S->top = S->base + S->stacksize;        S->stacksize += STACKADD;    }    *S->top++ = e;    return 1;}int Pop(SqStack* S,datatype* e){    if(StackEmpty(S))        return 0;    *e = *--S->top;    return 1;}