2019-01-31 Day26

1.移除链表元素
删除链表中等于给定值 val 的所有节点。

示例:

输入: 1->2->6->3->4->5->6, val = 6
输出: 1->2->3->4->5

/**
 * 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 * listhead = new ListNode(0);
        listhead ->next = head;
        ListNode * cur = head ,*headlist = listhead;
        
        while( cur )
        {
            if(cur -> val == val)
                listhead ->next = cur -> next;
            else
                listhead = listhead->next;
            cur = cur ->next;
        }
        
        return headlist->next;
        
    }
};