隊列例程

#include "stdio.h"
#include "stdlib.h"

#define Element int

struct QueueRecord;
typedef struct QueueRecord *Queue;

int IsEmpty(Queue Q); 
int Isfull(Queue Q);
Queue creat(int Maxsize);
void DisposeQueue(Queue Q);
void MakeEmpty(Queue Q);
void EnQueue(Element X,Queue Q);//入隊
void DeQueue(Queue Q);//出隊
Element ReturnQueue(Queue Q);//返回隊首元素

#define Minsize (5)

struct QueueRecord
{
	int capacity;//上限，可由Maxsize輸入控制，或利用define.
	int front;//隊首
	int rear;//隊尾
	int size;
	Element *Array;
};

int IsEmpty(Queue Q)
{
	return Q->size==0;//if Q->size==0, return it
}

int IsFull(Queue Q)
{
	if(Q->size==Q->capacity)
		return 0;
	else
		return 1;
}

Queue creat(int Maxsize)
{
	Queue Q;
	Q=(Queue)malloc(sizeof(struct QueueRecord));
	MakeEmpty(Q);
	Q->capacity=Maxsize;
	Q->Array=(Element*)malloc(sizeof(Element)*Maxsize);
	return Q;
}

void DisposeQueue(Queue Q)
{
	if(!IsEmpty(Q))
	{
		free(Q->Array);
		free(Q);
	}
}

void MakeEmpty(Queue Q)
{
	Q->size=0;
	Q->front=1;
	Q->rear=0;
}

int Succ(int Value,Queue Q)
{
	if(Value==Q->capacity)//若隊尾過界，重新置爲0，進行入隊
		Value=0;
	else
		Value++;
	return Value;//上一個if條件句
}

void EnQueue(Element X,Queue Q)
{
	if(IsFull(Q)==0)//若隊列滿(若循環隊列，此行需改變)
		printf("Queue has been full!\n");
	else
	{
		Q->size++;
		Q->rear=Succ(Q->rear,Q);//並非構建循環隊列 只是爲了防止rear或front超出數組範圍
		Q->Array[Q->rear]=X;
	}
}

void DeQueue(Queue Q)
{
	if(IsFull(Q)==0)
		printf("Queue has been full!\n");
	else
	{
		Q->size--;
		Q->front=Succ(Q->front,Q);
	}
}

Element ReturnQueue(Queue Q)
{
	return Q->Array[Q->front];
}

int main()
{
	Queue Q;
	int n;
	scanf("%d",&n);
	Q=creat(n);
	int x;
	int i;
	int temp;
	EnQueue(3,Q);
	EnQueue(4,Q);
	temp=ReturnQueue(Q);
	printf("%d\n",temp);
	DeQueue(Q);
	temp=ReturnQueue(Q);
	printf("%d\n",temp);
	return 0;
	
}