【数据结构】循环队列的表示和实现

以你之姓@ 2021-11-26 10:54 400阅读 0赞

#include<iostream>
    using namespace std;
    const int MAXSIZE = 10;
    typedef struct Queue {
        int data[MAXSIZE];
        int front;
        int rear;
    }Queue;
    
    void InitQueue(Queue &Q) {
        Q.rear = Q.front = 0;
    }
    
    bool QueueEmpty(Queue Q) {
        if (Q.rear == Q.front) {
            cout<<"Queue is empty"<<endl;
            return true;
        }
        return false;
    }
    
    bool QueueFull(Queue Q) {
        if ((Q.rear+1)%MAXSIZE == Q.front) {
            cout<<"Queue is full"<<endl;
            return true;
        }
        return false;
    }
    
    bool EnQueue(Queue &Q, int data) {
        if (QueueFull(Q)) {
            cout<<"Enqueue "<<data<<" fail"<<endl;
            return false;
        }
        Q.data[Q.rear] = data;
        Q.rear = (Q.rear+1)%MAXSIZE;
        return true;
    }
    
    bool DeQueue(Queue &Q, int &data) {
        if (QueueEmpty(Q))
            return false;
        data = Q.data[Q.front];
        Q.front = (Q.front+1)%MAXSIZE;
        return true;
    }
    
    void PrintQueue(Queue Q) {
        int ptr = Q.front;
        while (ptr != Q.rear) {
            cout<<Q.data[ptr]<<" ";
            ptr = (ptr+1)%MAXSIZE;
        }
        cout<<endl;
    }
    
    int main() {
        Queue Q;
        InitQueue(Q);
        cout<<"Enqueue 10 elements"<<endl;
        for (int i=0; i<10; i++)
            EnQueue(Q, i), PrintQueue(Q);
    
        cout<<endl<<"Dequeue 5 elements"<<endl;
        for (int i=0, e; i<5; i++) {
            DeQueue(Q, e);
            cout<<"After dequeue "<<e<<endl;
            PrintQueue(Q);
        }
        cout<<endl<<"Enqueue 2 elements"<<endl;
        for (int i=0; i<2; i++)
            EnQueue(Q, i), PrintQueue(Q);
        return 0;
    }

// 测试结果
    Enqueue 10 elements
    0
    0 1
    0 1 2
    0 1 2 3
    0 1 2 3 4
    0 1 2 3 4 5
    0 1 2 3 4 5 6
    0 1 2 3 4 5 6 7
    0 1 2 3 4 5 6 7 8
    Queue is full
    Enqueue 9 fail
    0 1 2 3 4 5 6 7 8
    
    Dequeue 5 elements
    After dequeue 0
    1 2 3 4 5 6 7 8
    After dequeue 1
    2 3 4 5 6 7 8
    After dequeue 2
    3 4 5 6 7 8
    After dequeue 3
    4 5 6 7 8
    After dequeue 4
    5 6 7 8
    
    Enqueue 2 elements
    5 6 7 8 0
    5 6 7 8 0 1