Python数据结构之环形队列

环形队列：主要解决假溢出现象；公式: rear = front = -1
添加数据 rear = (rear+1) % MAX_SIZE
删除数据 front = (front+1) % MAX_SIZE
判断空: rear == front
判断满 : (rear+1) % MAX_SIZE = front
判断数据个数: (rear - front + MAX_SIZE)%MAX_SIZE

加入数据

def enqueue(name):
    global rear
    global front

    rear = (rear + 1) % MAX_SIZE
    if rear != front:
        data_arr[rear] = name
    else:
        print("队伍已经为满！")

删除数据

def dequeue():
    global front

    front = (front + 1) % MAX_SIZE
    if rear != front:
        find_data = data_arr[front]
        data_arr[front] = None
        return find_data
    else:
        print("队列以空了！")
        return None

判断空和判断满

def is_empty():
    if rear == front:
        return True
    else:
        return False


def is_full():
    if (rear + 1) % MAX_SIZE == front:
        return True
    else:
        return False

总价：全部代码

front = rear = -1
MAX_SIZE = 6
data_arr = [None] * MAX_SIZE


def enqueue(name):
    global rear
    global front

    rear = (rear + 1) % MAX_SIZE
    if rear != front:
        data_arr[rear] = name
    else:
        print("队伍已经为满！")


def dequeue():
    global front

    front = (front + 1) % MAX_SIZE
    if rear != front:
        find_data = data_arr[front]
        data_arr[front] = None
        return find_data
    else:
        print("队列以空了！")
        return None


def is_empty():
    if rear == front:
        return True
    else:
        return False


def is_full():
    if (rear + 1) % MAX_SIZE == front:
        return True
    else:
        return False


if __name__ == '__main__':
    enqueue("dog")
    enqueue("dog")
    enqueue("dog")
    enqueue("dog")
    enqueue("dog")
    print(data_arr)
    dequeue()
    print(data_arr)