数据结构队列的基本操作-蒲公英云

数据结构队列的基本操作

矫情吗；* 2022-09-19 01:30 278阅读 0赞

#include <stdio.h>
#include <stdlib.h>
#define OK         1
#define ERROR      0
#define OVERFLOW   -2
typedef int QElemType;
typedef struct QNode
{
    QElemType data;
    struct QNode *next;
}QNode, *QueuePtr;
typedef struct
{
    QueuePtr front; /*Q.front相当于单链表的头结点，即Q.front->next是第一个数据*/
    QueuePtr rear; /*Q.rear指向最后一个数据,，即Q.rear->next = NULL*/
}LinkQueue;
int InitQueue(LinkQueue &Q)
{
    Q.front = Q.rear = (QueuePtr)malloc(sizeof(QNode));
    if (!Q.front)
    {
        exit(OVERFLOW);
    }
    Q.front ->next = NULL;
    return OK;
}
int EnQueue(LinkQueue &Q, QElemType e)
{
    QueuePtr p;
    p = (QueuePtr)malloc(sizeof(QNode));
    if (!p)
    {
        exit(OVERFLOW);
    }
    p->data = e;
    p->next = NULL;
    Q.rear ->next = p;/*插入第一个节点时，也是Q.front->next = p;*/
    Q.rear = p;/*队尾始终指向最后一个元素，即Q.rear->next = NULL*/
    return OK;
}
int DeQueue(LinkQueue &Q, QElemType &e)
{
    QueuePtr p;
    if (Q.front == Q.rear)
    {
        return ERROR;
    }
    p = Q.front->next;
    e = p->data;
    Q.front->next = p->next;
    if (Q.rear == p )
    {
        Q.rear = Q.front ;
    }
    free(p);
    return OK;
}
int DestroyQueue(LinkQueue &Q)
{
    while (Q.front)
    {
        Q.rear = Q.front->next ;
        free(Q.front);
        Q.front = Q.rear;
    }
    return OK;
}
int isQueue_Empty(LinkQueue Q)
{
    if (Q.front == Q.rear)
    {
        return 1;
    }
    return 0;
}
void Print_Queue(LinkQueue Q)
{
    if (isQueue_Empty(Q))
    {
        return;
    }
    while (Q.front != Q.rear)
    {
        printf("%d ",Q.front->next->data);
        Q.front = Q.front->next;
    }
    printf("\n");
}
int main()
{
    int i,n,e;
    LinkQueue Q;
    scanf("%d",&n);
    InitQueue(Q);
    for (i=0; i<n; i++)
    {
        scanf("%d",&e);
        EnQueue(Q, e);
    }
    Print_Queue(Q);
    DeQueue(Q,e);
    Print_Queue(Q);
    EnQueue(Q, 100);
    Print_Queue(Q);
    EnQueue(Q, 200);
    Print_Queue(Q);
    DestroyQueue(Q);
    return 0;
}