203. Remove Linked List Elements

QUESTION:

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

Credits: Special thanks to @mithmatt for adding this problem and creating all test cases.

EXPLANATION:

这个也是挺容易的，只是需要考虑如果第一个数就是对应值的情况。

SOLUTION:

public class Solution {
    public ListNode removeElements(ListNode head, int val) {
        while (head!=null && head.val == val){
            head = head.next;
        }
        ListNode pre = null;
        ListNode result = head;
        while (head!=null){
            if(head.val!=val){
                pre = head;
                head = head.next;
                continue;
            }
            pre.next = head.next;
            head = head.next;
        }
        return result;
    }
}
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