【LeetCode】203.Remove Linked List Elements

LeetCode-203

Link: https://leetcode.com/problems/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

思路：先保存下原串，然后依次寻找删除即可…（链表删除方法.）

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:
    ListNode* removeElements(ListNode* head, int val) {
        ListNode* newhead = new ListNode(-1);
        newhead->next = head;
        ListNode* it = newhead;
        
        while(it->next!=NULL)
        {
            if(it->next->val == val)
            {
                it->next=it->next->next;
            }
            else
            {
                it = it->next;
            }
        }
        
        return newhead->next;
    }
};

/**

* Definition for singly-linked list.

* struct ListNode {

* int val;

* ListNode *next;

* ListNode(int x) : val(x), next(NULL) {}

* };

class Solution {

public:

ListNode* removeElements(ListNode* head, int val) {

ListNode* newhead = new ListNode(-1);

newhead->next = head;

ListNode* it = newhead;

while(it->next!=NULL)

{

if(it->next->val == val)

{

it->next=it->next->next;

}

else

{

it = it->next;

}

return newhead->next;

}

};

【LeetCode】203.Remove Linked List Elements

Tagged on: LeetCode