队列--顺序存储

#include<stdio.h>

#define OK      1
#define ERROR   0
#define TRUE    1
#define FALSE   0

#define MAXSIZE 20
typedef int QElemType;
typedef int Status;

typedef struct {
    QElemType data[MAXSIZE];
    int front;
    int rear;
}Queue;

Status visit(QElemType e){
    printf("%d ",e);
    return OK;
}

Status InitQueue(Queue *Q){
    Q->front = 0;
    Q->rear = 0;   
}

Status QueueEmpty(Queue Q){
    //不要根据front和rear是否为0判断，因为可能是入队之后出队，front和rear都不为0
    if(Q.front == Q.rear){
        return TRUE;
    }
    return FALSE;
}

int QueueLength(Queue Q){
    return Q.rear - Q.front;
}

Status EnQueue(Queue *Q,QElemType e){
    if(Q->rear  >= MAXSIZE ){
        return ERROR;
    } 
    Q->data[Q->rear++] = e;
    return OK;
}

Status DeQueue(Queue *Q,QElemType *e){
    if(Q->front == Q->rear){
        return ERROR;
    }
    *e = Q->data[Q->front++];
    return OK;
}

Status QueueTraverse(Queue Q){
    if(Q.front == Q.rear){
        return ERROR;
    }
    int i = Q.front;
    while(i < Q.rear){
        visit(Q.data[i++]);
    }
    printf("\n");
    return OK;
}

int main(){
    QElemType e;
    Status i;
    int j;
    Queue Q;
    i = InitQueue(&Q);
    if(i){
        printf("初始化成功\n");
    } else {
        printf("初始化失败\n");
    }
    printf("队列是否为空 %d \t 长度 %d\n",QueueEmpty(Q),QueueLength(Q));

    for(j = 0; j < 25; j++){
        EnQueue(&Q,j);
    }
    printf("队列是否为空 %d \t 长度 %d\n",QueueEmpty(Q),QueueLength(Q));
    QueueTraverse(Q);

    DeQueue(&Q,&e);
    printf("出队元素是 %d\n",e);
    printf("队列是否为空 %d \t 长度 %d\n",QueueEmpty(Q),QueueLength(Q));
    QueueTraverse(Q);
    return 0;
}