Preface

The following basic operations of circular queue are programmed ： Build a queue , Take the team leader element , The team , Out of the team .
Want to know the detailed explanation of circular queue Please order me
️ Personal home page ： Collection and attention , Never get lost ~ ️
Now let's take a look at how to realize it

One 、 Code implementation

#include <iostream>

using namespace std;

#define ERROR -1
#define OK 1

typedef int QElemType;
typedef int Status;

// Storage structure of circular queue 
#define MAXQSIZE 100 // Maximum queue length 
typedef  struct
{
    
    QElemType *base;       // Used to dynamically allocate storage space 
    int  front;            // Team leader index 
    int  rear;             // End of team index 
} SqQueue;

// initialization 
void InitQueue (SqQueue &Q)
{
    
    // Construct an empty queue 
    Q.base =new QElemType[MAXQSIZE];
    Q.front=Q.rear=0;
}

// Destroy queue 
void DestroyQueue(SqQueue &Q)
{
    
    if(Q.base)
        free(Q.base);
    Q.base = NULL;
    Q.front = Q.rear = 0;
}

// Clear queue 
void ClearQueue(SqQueue &Q)
{
    
    Q.front=Q.rear=0;
}
// Find the length 
int  QueueLength (SqQueue Q)
{
    
    return (Q.rear-Q.front+MAXQSIZE)%MAXQSIZE;
}

// Sentenced to empty 
bool QueueEmpty (SqQueue Q)
{
    
    return (Q.front==Q.rear);
}

// Find the team head element 
Status GetHead (SqQueue Q, QElemType &e)
{
    
    if(Q.front==Q.rear) return ERROR;
    e=Q.base[Q.front];
    return OK;
}

// Loop queue in 
Status EnQueue(SqQueue &Q,QElemType e)
{
    
    if((Q.rear+1)%MAXQSIZE==Q.front)  return ERROR;
    Q.base[Q.rear]=e;
    Q.rear = (Q.rear+1) % MAXQSIZE;
    return OK;
}

// Loop queue out 
Status DeQueue (SqQueue &Q,QElemType &e)
{
    
    if(Q.front==Q.rear) return ERROR;
    e=Q.base[Q.front];
    Q.front=(Q.front+1) % MAXQSIZE;
    return OK;
}

// Traversal causes the queue to display 
void DisplayQueue(SqQueue Q)
{
    
    int i=Q.front;
    while(Q.front!=Q.rear && (i+MAXQSIZE) % MAXQSIZE != Q.rear)
    {
    
        cout<<Q.base[i]<<endl;
        i++;
    }
}
void show_help()
{
    
    cout<<"******* Data Structure ******"<<endl;
    cout<<"1---- Empty the circular queue "<<endl;
    cout<<"2---- Determine whether the circular queue is empty "<<endl;
    cout<<"3---- Find the length of the loop queue "<<endl;
    cout<<"4---- Take the team leader element "<<endl;
    cout<<"5---- The team "<<endl;
    cout<<"6---- Out of the team "<<endl;
    cout<<"7---- Show queue "<<endl;
    cout<<"  sign out , Input 0"<<endl;

}
int main()
{
    
    char operate_code;
    show_help();
    SqQueue Q;
    InitQueue(Q);
    QElemType e;
    int i;
    while(1)
    {
    
        cout<<" Please enter the operation code :";
        cin>>operate_code;
        if(operate_code=='1')
        {
    
            cout<<"The queue has been cleared."<<endl;
            ClearQueue(Q);

        }
        else if (operate_code=='2')
        {
    
            if(QueueEmpty(Q))
                cout<<"The queue is empty."<<endl;
            else
                cout<<"The queue is not empty."<<endl;

        }
        else if (operate_code=='3')
        {
    
            cout<<"The length of queue is:"<<QueueLength(Q)<<endl;

        }
        else if (operate_code=='4')
        {
    
            cout<<" The team leader element is ："<<endl;
            if(GetHead(Q,e) == 1) cout<<e<<endl;
            else cout <<"error"<<endl;
        }
        else if (operate_code=='5')
        {
    
            cout<<" Please enter the number of you want to join the team ："<<endl;
            cin>>e;
            EnQueue(Q,e);
        }
        else if (operate_code=='6')
        {
    
            cout<<" The outgoing element is ："<<endl;
            if(DeQueue(Q,e)) cout<<e<<endl;
        }
        else if (operate_code=='7')
        {
    
            cout<<"The contents of the queue are:"<<endl;
            DisplayQueue(Q);
        }
        else if (operate_code=='0')
        {
    
            break;
        }
        else
        {
    
            cout<<"\n Opcode error ！！！"<<endl;
            show_help();
        }
    }
    // Call the destroy stack function 
    DestroyQueue(Q);
    return 0;
}

Two 、 Running results

summary

This paper is used to introduce the code implementation process and running result example of circular queue in data structure . Displays the initialization of the circular queue in a menu style 、 Empty 、 The destruction 、 Find the length 、 Find the team head element 、 Sentenced to empty 、 The team 、 Out of the queue and traverse the queue to display .