queue.h

大三计算机的数据结构的 c++ 所用的 头文件

#include "iostream.h"
#include "stdio.h"
#include "malloc.h"

#define TRUE 1
#define FALSE 0
#define OK 1
#define ERROR 0
#define INFEASIBLE -1
#define OVERFLOW -2
#define NULL 0

typedef int Status;
typedef int QElemType;

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

typedef struct{
	QueuePtr front; //队列的头指针
	QueuePtr rear;// 队列的尾指针
}LinkQueue;

Status InitQueue (LinkQueue &Q) {
   // 构造一个空队列Q
   Q.front = Q.rear = new  QNode;
   if (!Q.front) return OVERFLOW; //存储分配失败                                         
   Q.front->next = NULL;
   return OK;
}
Status DestoryQueue(LinkQueue &Q)
{
	while(Q.front) 
	{  
		Q.rear=Q.front->next;
		free(Q.front);
		Q.front=Q.rear;
	}
	return OK;
}

Status QueueEmpty(LinkQueue Q)
{
	if (Q.front == Q.rear)    return TRUE;
	  else return FALSE;
}

int QueueLength(LinkQueue Q)
{
	QNode *p;  int i=0;
	p=Q.front->next;
	while(p!=NULL)
	{
		p=p->next;  i++;
	}
	return i;
}

Status EnQueue (LinkQueue &Q, QElemType e) {
    // 插入元素e为Q的新的队尾元素
    QNode *p;
	p =  new QNode;
    if (!p)  return OVERFLOW;   //存储分配失败
    p->data = e;   p->next = NULL;
    Q.rear->next = p;    Q.rear = p;
    return OK;
}

Status DeQueue (LinkQueue &Q, QElemType &e) {
  // 若队列不空，则删除Q的队头元素，用 e 返回其值，并返回OK；否则返回ERROR
   QNode *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;
   delete (p);      return OK;
}