栈的基本操作

#include
#include

//栈结点的定义
typedef struct stacknode
{
    char data;
    struct stacknode *next;
}stacknode;

//构造空栈
stacknode* creat_stack()
{
    stacknode *top = NULL;
    return top;
}

//入栈
stacknode* push(stacknode *top, char data)  //在栈顶元素插入元素data
{
    stacknode *p = (stacknode *)malloc(sizeof(stacknode));      //生成一个新节点
    p->data = data;
    p->next = top;
    top = p;
    return top;
}

//出栈
stacknode* pop(stacknode *top, char *t)    //用t返回其值
{
    stacknode *p = NULL;
    if (top == NULL)
    {
        printf("栈为空，无法出栈！\n");
        return NULL;
    }
    *t = top->data;
    p = top;
    top = top->next;
    printf("元素%c已出栈\n", *t);
    free(p);
    return top;
}

//显示栈
void output(stacknode *top)
{
    if (top == NULL)
        printf("栈为空\n");
    else
    {
        stacknode *p = (stacknode *)malloc(sizeof(stacknode));
        p = top;
        printf("栈遍历为:");
        while(p != NULL)
        {
            printf("%c ", p->data);
            p = p->next;
        }
        free(p);
        printf("\n");
    }
}

//求栈的结点个数
void Node_count(stacknode *top)
{
    int count = 0;
    stacknode *temp = top;
    while(temp != NULL)
    {
        count++;
        temp = temp->next;
    }
    printf("栈的结点个数为%d\n", count);
}

//销毁栈
stacknode* Destroy_stack(stacknode *top)
{
    if(top == NULL)
        printf("栈为空，无法销毁!\n");
    else
    {
        stacknode *temp;
        while(top != NULL)
        {
            temp = top->next;
            free(top);
            top = temp;
        }
        printf("栈已销毁!\n");
    }
    return NULL;
}

int main()
{
    stacknode *top = creat_stack(); //建立一个空栈

    printf("               栈子系统\n");
    printf("**************************************************\n");
    printf("*          1-----入栈                            *\n");
    printf("*          2-----出栈                            *\n");
    printf("*          3-----显示栈                          *\n");
    printf("*          4-----求栈的结点个数                  *\n");
    printf("*          5-----销毁栈                          *\n");
    printf("*          0-----结束                            *\n");
    printf("**************************************************\n");

    while (1)
    {
        int ch;
        printf("\n***************************************************\n");
        printf("请输入你要进行的操作对应的数字：");
        scanf("%d",&ch);
        getchar();
        switch(ch)
        {
            case 1:         //入栈
                {
                    char data;
                    printf("请输入要入栈的元素:");
                    scanf("%c", &data);
                    getchar();
                    top = push(top, data);
                    printf("元素%c已入栈\n", data);
                    break;
                }

            case 2:     //出栈
                {
                    char t = 0; //*t用来接收出栈的值;
                    top = pop(top, &t);
                    break;
                }

            case 3:         //显示栈
                {
                    output(top);
                    break;
                }
            case 4:         //求栈的结点个数
                {
                    Node_count(top);
                    break;
                }
            case 5:         //销毁栈
                {
                    top = Destroy_stack(top);
                    break;
                }
            case 0:
                {
                    printf("程序已结束!\n");
                    return 0;
                }
            default:
                {
                    printf("输入的数值有误，请重新输入\n");
                    break;
                }
        }
    }
    return 0;
}



//
//                          _ooOoo_
//                         o8888888o
//                         88" . "88
//                         (| ^_^ |)
//                         O\  =  /O
//                      ____/`---'\____
//                    .'  \\|     |//  `.
//                   /  \\|||  :  |||//  \
//                  /  _||||| -:- |||||-  \
//                  |   | \\\  -  /// |   |
//                  | \_|  ''\---/''  |   |
//                  \  .-\__  `-`  ___/-. /
//                ___`. .'  /--.--\  `. . ___
//              ."" '<  `.___\_<|>_/___.'  >'"".
//            | | :  `- \`.;`\ _ /`;.`/ - ` : | |
//            \  \ `-.   \_ __\ /__ _/   .-` /  /
//      ========`-.____`-.___\_____/___.-`____.-'========
//                           `=---='
//      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
//                     佛祖保佑     永无BUG
//