203. Remove Linked List Elements
Tags: ‘Linked List’
Remove all elements from a linked list of integers that have value val.
Example:
Input: 1->2->6->3->4->5->6, val = 6 Output: 1->2->3->4->5
Solution
Mind corner cases. 遇事不决画个图
public ListNode removeElements(ListNode head, int val) {
if (head == null) return null;
ListNode dummy = new ListNode(-1);
dummy.next = head;
ListNode curr = head, prev = dummy;
while (curr != null) {
if (curr.val == val) {
prev.next = curr.next;
curr = curr.next;
} else {
prev = prev.next;
curr = curr.next;
}
}
return dummy.next;
}