数据结构之循环队列

#include<iostream>
using namespace std;
#define QSIZE 8
typedef int ElemType;
typedef struct {
ElemType *pBase;
int Front;
int Rear;
}Queue;//循环队列比顺序对要节省大量的空间，默认是不用顺序队的
void InitQueue(Queue &Q)
{
Q.pBase = new ElemType[QSIZE];
Q.Front = 0;
Q.Rear = 0;
}
void DestroyQueue(Queue &Q)
{
delete[]Q.pBase;
Q.Front = 0;
Q.Rear = 0;
return;
}
void ClearQueue(Queue &Q)
{
Q.Front = 0;
Q.Rear = 0;
return;
}
bool QueueFull(Queue &Q)//浪费一个单元为代价，当处理大量的数据时是非常值得的.
{
if ((Q.Rear + 1) % QSIZE == Q.Front)
return true;
else
return false;
}
bool QueueEmpty(Queue &Q)
{
if (Q.Front == Q.Rear)
return true;
else
return false;
}
int QueueLength(Queue &Q)
{
if (QueueEmpty(Q))
return 0;
else
return (Q.Rear - Q.Front + QSIZE) % QSIZE;
}
bool GetHead(Queue Q, ElemType &e)
{
if (QueueEmpty(Q))
return false;
e = Q.pBase[Q.Front];
return true;
}
bool EnQueue(Queue &Q, ElemType e)
{
if (QueueFull(Q))
return false;
Q.pBase[Q.Rear] = e;
Q.Rear = (Q.Rear + 1) % QSIZE;
return true;
}
bool DeQueue(Queue &Q, ElemType &e)
{
if (QueueEmpty(Q))
return false;
e = Q.pBase[Q.Front];
Q.Front = (Q.Front + 1) % QSIZE;
return true;
}
void Visit(ElemType e)
{
cout << e << " ";
}
void Traverse(Queue Q)
{
int i = Q.Front;
while (i != Q.Rear)
{
Visit(Q.pBase[i]);
i = (i + 1) % QSIZE;
}
cout << endl;
return;
}
int main(void)
{
Queue Q;
ElemType e = 0;
InitQueue(Q);
EnQueue(Q, 1);
EnQueue(Q, 2);
EnQueue(Q, 3);
EnQueue(Q, 4);
EnQueue(Q, 5);
EnQueue(Q, 6);
GetHead(Q, e);
cout << e << endl;
Traverse(Q);
if (QueueEmpty(Q))
cout << "Indeed Empty!" << endl;
else
cout << "Not Empty!" << endl;
cout << QueueLength(Q) << endl;
EnQueue(Q, 7);
//注意：7个数据则队便满，EnQueue(Q, 8)无效
if (QueueFull(Q))
cout << "Indeed Full!" << endl;
else
cout << "Not Full!" << endl;
Traverse(Q);
DeQueue(Q, e);
cout << e << endl;
Traverse(Q);
return(0);
}