[LeetCode]--203. 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

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

深夜来了一发，Accept了。

public ListNode removeElements(ListNode head, int val) {
        if (head == null)
            return null;
        while (head.val == val && head.next != null)
            head = head.next;
        if (head.val == val && head.next == null)
            return null;
        if (head.next != null) {
            ListNode temp = head, p = head.next;
            while (p != null) {
                if (p.val == val)
                    temp.next = p.next;
                else
                    temp = temp.next;
                p = temp.next;
            }
        }
        return head;
    }

学习一下别人的算法。

public ListNode removeElements(ListNode head, int val) {
        ListNode dummy = new ListNode(0);
        dummy.next = head;
        head = dummy;

        while (head.next != null) {
            if (head.next.val == val) {
                head.next = head.next.next;
            } else {
                head = head.next;
            }
        }
        return dummy.next;
    }