c++实现循环队列的长度并运行结果

循环队列长度的实现代码如下：

#include<iostream>
using namespace std;

class CircularQueue{
private:
    int front; // 队头指针
    int rear; // 队尾指针
    int size; // 队列长度
    int *data; // 队列数组
public:
    CircularQueue(int k){
        front = 0;
        rear = 0;
        size = k+1; // 为了区分队空和队满，数组长度要比队列长度多1
        data = new int[size];
    }
    ~CircularQueue(){
        delete[] data;
    }
    bool isEmpty(){
        return front == rear;
    }
    bool isFull(){
        return (rear+1)%size == front;
    }
    void enqueue(int value){
        if(isFull()){
            cout<<"Queue is Full"<<endl;
            return;
        }
        data[rear] = value;
        rear = (rear+1)%size;
    }
    int dequeue(){
        if(isEmpty()){
            cout<<"Queue is Empty"<<endl;
            return -1;
        }
        int res = data[front];
        front = (front+1)%size;
        return res;
    }
    int getLength(){
        return (rear-front+size)%size;
    }
};

int main(){
    CircularQueue cq(3);
    cq.enqueue(1);
    cq.enqueue(2);
    cq.enqueue(3);
    cout<<"Length: "<<cq.getLength()<<endl; // 输出队列长度
    cq.dequeue();
    cout<<"Length: "<<cq.getLength()<<endl;
    cq.dequeue();
    cout<<"Length: "<<cq.getLength()<<endl;
    cq.dequeue();
    cout<<"Length: "<<cq.getLength()<<endl;
    cq.dequeue();
    cout<<"Length: "<<cq.getLength()<<endl;
    return 0;
}

运行结果如下：

Length: 3
Length: 2
Length: 1
Length: 0
Queue is Empty
Length: 0