[数据结构-严蔚敏版]P61ADT Queue的表示与实现(单链队列-队列的链式存储结构)

Posted 2021-09-03 Wecccccccc

代码如下:

#include <iostream>
using namespace std;

typedef int ElemType;

typedef struct QNode
{
	ElemType data;
	QNode *next;
}QNode ,*QueuePtr;

typedef struct
{
	QueuePtr front;
	QueuePtr rear;
}LinkQueue;

bool initQueue(LinkQueue &q)
{
	q.front = q.rear = new QNode;
	if (!q.front) return false;
	q.front->next = nullptr;
	return true;
}

bool destroy(LinkQueue &q)
{
	while (q.front)
	{
		q.rear = q.front->next;
		delete q.front;
		q.front = q.rear;
	}
	q.front = q.rear = nullptr;
	return true;
}

bool clearQueue(LinkQueue &q)
{
	QNode *p = q.front->next;
	QNode *s = nullptr;
	while (p)
	{
		s = p;
		p = p->next;
		delete s;
	}
	q.rear = q.front;
	return true;
}

bool queueEmpty(LinkQueue q)
{
	if (q.front == q.rear) return true;
	return false;
}

int queueLength(LinkQueue q)
{
	int j = 0;
	QNode *p = q.front->next;
	while (p)
	{
		j++;
		p = p->next;
	}
	return j;
}

bool getHead(LinkQueue q, ElemType &e)
{
	if (q.front == q.rear) return false;
	e = q.front->next->data;
	return true;
}

bool enQueue(LinkQueue &q, ElemType e)
{
	QNode *p = new QNode;
	if (!p) return false;
	p->data = e;
	p->next = nullptr;
	q.rear->next = p;
	q.rear = p;
	return true;
}

bool deQueue(LinkQueue &q, ElemType &e)
{
	if (q.front == q.rear) return false;
	QNode *p = q.front->next;
	q.front->next = p->next;
	if (q.rear == p)q.rear = q.front;
	delete p;
	return true;
}


void vis(ElemType e)
{
	cout << e << " ";
}

void queueTraverse(LinkQueue q, void(*visit)(ElemType))
{
	QNode *p = q.front->next;
	while (p)
	{
		visit(p->data);
		p = p->next;
	}
}

int main() {
	LinkQueue q;
	initQueue(q);
	int n;
	int a;
	cin >> n;
	for (int i = 0; i < n; i++)
	{
		cin >> a;
		enQueue(q, a);
	}
	queueTraverse(q, vis);
	cout << endl;
	deQueue(q, a);
	deQueue(q, a);
	queueTraverse(q, vis);
	cout << endl;
	cout << queueLength(q) << endl;
	return 0;
}