数据结构队列的基本操作

矫情吗；* 2022-09-19 01:30 213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;
    }