[数据结构与算法]队列的基本操作

title: 队列的基本操作
mathjax: true
date: 2021-10-28 20:53:24
tags: “数据结构作业”
description: wls队列的基本操作

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
// 队列的节点 
struct Node
{
        int data;
        struct Node* next;
};
// 队首队尾指针 
struct Queue
{
        struct Node* front;
        struct Node* rear;
        int size;
};
 
void QueueInit(struct Queue* queue)
{
        queue->front = NULL;
        queue->rear = NULL;
        queue->size = 0;
}
 
int QueueEmpty(struct Queue* queue)
{
        return (queue->size == 0);
}
 
void QueuePush(struct Queue* queue, const int data)
{
        struct Node* node;
        node = (struct Node*)malloc(sizeof(struct Node));
        assert(node != NULL);
        
        node->data = data;
        node->next = NULL;
        
        if(QueueEmpty(queue))
        {
            queue->front = node;
            queue->rear = node;
        }
        else
        {            
            queue->rear->next = node;
            queue->rear = node;
        }
        ++queue->size;
}

int QueuePop(struct Queue* queue, int* data)
{
        if (QueueEmpty(queue))
        {
                return 0;
        }
        struct Node* tmp = queue->front;
        *data = queue->front->data;
        queue->front = queue->front->next;
        free(tmp);
        --queue->size;
 
        return 1;
}
 
void QueueDestroy(struct Queue* queue)
{
     struct Node* tmp;
     while(queue->front)
     {
         tmp = queue->front;
         queue->front = queue->front->next;
         free(tmp);
     }
}

//show all ele
int _deplay(struct Queue queue)
{
    if (queue.size == 0) {
        return 0;
    }
    struct Node *p = queue.front;
    while(p)
    {
        printf("%d " , p -> data);
        p = p -> next;
    }
    printf("\n");
    return 1;
}

void deplay(struct  Queue queue) 
{
    if (_deplay(queue) == 0 ) 
    {
        printf("队列为空.\n");
        return ;
    }
    else {
        printf("遍历结束.\n");
    }
}

void menu(struct Queue queue)
{
    while(1) {
            int op , x;
            printf("1.插入        2.弹出\n");
            printf("3.遍历        4.销毁\n");
            printf("5.得到头元素   6.是否为空\n");
            printf("7.长度\n");
            printf("请输入操作序号：");
            scanf("%d" , &op);
            switch (op)
            {
                case 1:
                    printf("请输入您要插入的元素.\n");
                    scanf("%d" , &x);
                    QueuePush(&queue, x);
                    break;
                case 2:
                    if(QueuePop(&queue, &x))printf("%d 已经被弹出队列.\n" , x);
                    else printf("队列已空.\n");
                    break;
                case 3:
                    deplay(queue);
                    break;
                case 4:
                    QueueDestroy(&queue);
                    printf("已经销毁.\n");
                    break;
                case 5:
                    printf("头元素为:%d\n" , queue.front -> data);
                    break;
                case 6:
                    if(QueueEmpty(&queue)) printf("为空\n");
                    else printf("不为空\n");
                    break;
                case 7:
                    printf("当前长度为：%d\n" , queue.size);
                    break;
                default:
                    printf("请输入正常的操作序号\n");
                    menu(queue);
                    break;
            }
        }
}
 
int main(void)
{
    //得到头 ， 遍历 ， 
        struct Queue queue;
        QueueInit(&queue);
        menu(queue);
        return 0;
}