LeetCode OJ 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.

struct ListNode * removeElements(struct ListNode * head, int val) {
	struct ListNode BeforeHead;
	struct ListNode * temp1 = head, *temp2 = &BeforeHead;
	BeforeHead.next = head;
	while (temp1 != NULL) {
		if (temp1->val != val) {
			temp2->next = temp1;
			temp2 = temp2->next;
		}
		temp1 = temp1->next;
	}
	temp2->next = NULL;
	return BeforeHead.next;
}