leetcode-203. Remove Linked List Elements-C++

1. Remove Linked List Elements
   Remove all elements from a linked list of integers that have value val.

Example
Given: 1 –> 2 –> 6 –> 3 –> 4 –> 5 –> 6, val = 6
Return: 1 –> 2 –> 3 –> 4 –> 5

class Solution {
public:
    ListNode* removeElements(ListNode* head, int val) {
    //思路：
    //如果下一个节点的val和给定val相等，则移除此节点

    //dummyNode为虚拟节点，放在本来的head头节点之前，方便操作
        ListNode* dummyNode = new ListNode(0);
        dummyNode->next = head;
        ListNode* curNode =dummyNode;
        while(curNdoe->next !=NULL){
            if(curNode->next->val == val){
                ListNode* delNode = curNode->next;
                curNode->next = delNode->next;
                delete delNode;
            }
            else
                curNode = curNode->next;
        }
        return dummyNode->next;
    }
};

附上链表常用操作便于检验代码正误

//结构体
struct ListNode{
    int val;
    ListNode* next;
    ListNode(int x):val(x),next(NULL){}
};

//创建链表
ListNode* createLinkedList(int arr[],int n){
    if(n ==0){
        return NULL;
    }

    ListNode* head = new ListNode(arr[0]);
    ListNode* curNode = head;
    for(int i = 1; i < n; i++){
        curNode->next = new ListNode(arr[i]);
        curNode = curNode->next;
    }

    return head;
}

//打印链表
void printLinkedList(ListNode* head){
    ListNode* curNode = head;
    while(curNode != NULL){
        cout << curNode->val << "->";
        curNode = curNode->next;
    }
    cout << "NULL";
    cout << endl;
}

//清除缓存
void deletelinkedList(ListNode* head){
    ListNode* curNode =head;
    while(curNode != NULL){
        ListNode* delNode =curNode;
        curNode = curNode->next;
        delete delNode;
    }
}