源代码如下:

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

#define OK 1
#define ERROR 0
#define MAXSIZE 50

typedef int SElementType;
typedef int Status;
typedef struct{
    SElementType data[MAXSIZE];
    int top1;
    int top2;
}SqDoubleStack;

void InitStack(SqDoubleStack *S){
    S->top1 = -1;
    S->top2 = MAXSIZE;
}

Status Push(SqDoubleStack *S, SElementType e, int stackNumber){
    if( (S->top2 - S->top1) == 1 ){
        return ERROR;
    }
    if(stackNumber == 1){
        S->data[++S->top1] = e;
    } else if(stackNumber == 2) {
        S->data[--S->top2] = e;
    }
    return OK;
}

Status Pop(SqDoubleStack *S,SElementType *e, int stackNumber){
    if(stackNumber == 1){
        if(S->top1 == -1){
            return ERROR;
        }
        *e = S->data[S->top1];
        S->top1--;
    } else if (stackNumber == 2){
        if(S->top2 == MAXSIZE){
            return ERROR;
        }
        *e = S->data[S->top2++];
    }
    return OK;
}

int StackLength(SqDoubleStack *S){
    return (S->top1 + 1 + MAXSIZE - S->top2);
}

int main(){
    SqDoubleStack *S = NULL;
    //SElementType *e = NULL;
    int i = 0;
    int stackNumber = 1;
    Status sts = OK;
    S = (SqDoubleStack*)malloc(sizeof(SqDoubleStack));
    //e = (SElementType*)malloc(sizeof(SElementType));
    if((S == NULL) /*|| (e == NULL)*/){
        printf("malloc failure.");
        return 0;
    }
    for(i = 0; i < 10; i++){
        stackNumber = (i%2==0) ? 1 : 2;
        sts = Push(S,i+1,stackNumber);
        printf("push:%d,sts:%d,stackNumber:%d",i+1,sts,stackNumber);
    }
    printf("stack double length:%d",StackLength(S));
    return 0;
}

错误截图如下：

程序调试发现执行到下面这行代码崩溃了


上次也碰到崩溃问题，有大神指点是因为指针变量没有申请内存，这次检查了很多遍，发现有申请，不知道是哪里出问题了

哪个地方加上括号啊，请指点下哈

主要是为了理解方便，一看就知道函数的返回是啥，代码就能起到很好的注释作用

确实初始化之后，程序不崩溃了，这个是为啥呢，我不是通过malloc分配了内存嘛，以前写脚本的，刚转到C上来。。。