一个双向链表的实现

来源：互联网发布：淘宝店刷一颗钻多少钱编辑：程序博客网时间：2024/06/11 02:17

问题来源：http://topic.csdn.net/u/20080423/00/c5530034-9327-47ea-baaa-07c39a61b756.html

本来是想改改算了，最后变成全部重写。既然都是自己写的，也算是原创吧！

代码贴在这儿。随手写的，有些地方不是很合理，也没经过测试。姑且供大家参考。

struct node
{
    int data;
    struct node *next;
    struct node *prior;

    node(int val = 0):data(val),next(0),prior(0){next = prior = this;}
    node(int val,node * nextNode, node * priorNode):data(val),next(nextNode),prior(priorNode){}
};

node * headnode=new node;

node * CreateDLink(node * head){
    int val;
    node * currNode;
    for(cin>>val;val != 0;cin>>val){
        currNode = new node(val,head,head->prior->prior);
        head->prior->next = currNode;
        head->prior = currNode;
    }
    return (headnode);
}

void ListDLink(node * head){
    node * currNode;
    cout <<"now the items of list are: ";
    for(currNode = head->next;currNode != head;currNode = currNode->next)
    {
        cout <<currNode->data <<' ';
    }
    cout<<endl;
}

int GetNodeCount(node * head){
    int count;
    node * currNode;
    for(count = 0,currNode = head->next;currNode != head;currNode = currNode->next,count++);
    return count;
}

node * GetNodeByIndex(node *head, int idx){
    int count;
    node * currNode;
    for(count = 0,currNode = head->next;currNode != head;currNode = currNode->next,count++){
        if(count == idx){
            return currNode;
        }
    }
    return NULL;
}

int GetNodeValueByIndex(node *head, int idx){
    node * targetNode = GetNodeByIndex(head, idx);
    if(targetNode)return targetNode->data;
    return -1;
}

node * GetNodeByValue(node *head, int val){
    node * currNode;
    for(currNode = head->next;currNode != head;currNode = currNode->next){
        if(currNode->data == val){
            return currNode;
        }
    }
    return NULL;
}

int GetNodeIndexByValue(node * head, int val){
    int count;
    node * currNode;
    for(count = 0,currNode = head->next;currNode != head;currNode = currNode->next,count++){
        if(currNode->data == val){
            return count;
        }
    }
    return -1;
}

node * InsertNode(node *posNode, int x){
    node * newNode = NULL;
    if(posNode){
        newNode = new node(x, posNode->next, posNode);
        posNode->next->prior = newNode;
        posNode->next = newNode;
    }
    return newNode;
}

node * InsertNode (node *head,int idx,int x){
    node *posNode = GetNodeByIndex(head, idx);
    return InsertNode(posNode, x);
}

bool DelNode(node * delNode){
    if(delNode){
        delNode->next->prior = delNode->prior;
        delNode->prior->next = delNode->next;
        delete delNode;
        return true;
    }
    return false;
}

bool DelNodeByIndex(node *head, int idx){
    node * targetNode = GetNodeByIndex(head, idx);
    if(targetNode && targetNode != head){
        return DelNode(targetNode);
    }
    return false;
}

bool DelNodeByValue(node *head, int val){
    node * targetNode = GetNodeByValue(head, val);
    if(targetNode && targetNode != head){
        return DelNode(targetNode);
    }
    return false;
}