連結串列4: 迴圈連結串列

連結串列4-迴圈連結串列

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迴圈連結串列的特點: 連結串列的尾結點後繼指向頭結點

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迴圈連結串列的結構

typedef struct Node{
    int data; //資料域
    struct Node *nextNode; //後繼
} Node;

迴圈連結串列的初始化

Node* initHeader(){
    //建立頭結點
    Node *header = (Node*)malloc(sizeof(Node));
    //頭結點的資料(用於儲存連結串列長度)
    header->data = 0;
    //頭結點的後繼
    header->nextNode = header;
    //返回
    return header;
}

後插法新增元素

//後插法新增元素(返回尾結點)
Node* addNode(Node *header, Node *roar){
    //空連結串列
    if(!header){
        cout << "連結串列不存在!" << endl;
        return NULL;
    }
    //開闢空間
    Node *newNode = (Node*)malloc(sizeof(Node));
    //賦值 
    cout << "輸入值" << endl;
    cin >> newNode->data;
    newNode->nextNode = NULL;
    //尾結點後繼指向新結點
    roar->nextNode = newNode;
    //新結點後繼指向header
    newNode->nextNode = header;
    //更新連結串列長度
    header->data++;
    //更新尾結點
    return newNode;
}

連結串列長度

void sizeOfLinkList(Node *header){
    //空連結串列
    if(!header){
        cout << "連結串列不存在!" << endl;
        return;
    }  
    cout << "連結串列長度: " << header->data << endl;
}

輸出連結串列

void display(Node *header){
    //空連結串列
    if(!header){
        cout << "連結串列不存在!" << endl;
        return;
    }    
    Node *curNode = header->nextNode;
    while(curNode!=header){
        cout << curNode->data << " ";
        //前進
        curNode = curNode->nextNode;
    }
    cout << endl;
}

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測試

int main(){
    int choice;
    Node *header=NULL;
    Node *roar=NULL;
    int length=0;

    do{
        cout << "--------------" << endl;
        cout << "1.建立" << endl;
        cout << "2.在尾部插入新節點" << endl;
        cout << "3.輸出連結串列" << endl;
        cout << "0.退出" << endl;
        cout << "輸入選項:";
        cin >> choice;
        switch(choice){
            case 1:
                header = initHeader();
                roar = header;
                break;
            case 2:
                roar = addNode(header, roar, length);
                break;
            case 3:
                display(header);
                break;
            default:
                break;
        }
    }while(choice!=0);

    system("pause");
    return 0;
}