C语言—链队列

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

typedef int	QElemType;
typedef struct Qnode {
	QElemType data;			//数据域
	struct Qnode *next;		//队列指针域
}QNode, *QueuePtr;

typedef struct {
	QueuePtr front; 	//队列头指针
	QueuePtr rear;		//队列尾指针
}LinkQueue;

void	InitQueue(LinkQueue &Q) {		//构造队列
	Q.front = Q.rear = (QueuePtr)malloc(sizeof(QNode));
	if(!Q.front) {
		printf("队列构造失败，程序退出！");
		exit(!0);
	}
	Q.front -> next = NULL;
}

void	DestroyQueue(LinkQueue &Q) {	//销毁队列
	while(Q.front) {
		Q.rear = Q.front -> next;
		free(Q.front);
		Q.front = Q.rear;
	}
	printf("\n\n队列已销毁！\n\n");
}

void	EnQueue(LinkQueue &Q,QElemType e) {		//插入元素
	QueuePtr p;
	p = (QueuePtr)malloc(sizeof(QNode));
	if(!p) {
		printf("存储空间分配失败，程序退出！");
		exit(!0);
	}
	printf("请输入进队列的值：");
	scanf("%d",&e);
	p -> data = e;
	p -> next = NULL;
	Q.rear -> next = p;
	Q.rear = p;
}


void	DeQueue(LinkQueue &Q, QElemType &e) {	//出队列操作
	QueuePtr p;
	if(Q.front == Q.rear) {
		printf("队列为空，无法执行出队操作，程序退出！");
		exit(!0);
	}
	p = Q.front->next;
	e = p -> data;
	Q.front -> next = p -> next;
	printf("\n出队元素为：%d\n",e);
	if(Q.rear == p) {
		Q.front = Q.rear;
		printf("队列内最后一个元素已出队\n");
	}
	free(p);
}

int	main() {
	LinkQueue Q;
	QElemType e;
	int num;

	InitQueue(Q);	//构造队列
	printf("请输入进入队列数量：");
	scanf("%d",&num);
	for(int i=1;i <= num;i++) {
		EnQueue(Q,e);	//插入元素
	}
	DeQueue(Q,e);		//第一个元素出队列
//	DestroyQueue(Q);	//销毁队列
	return 0;
}