203. Remove Linked List Elements

https://leetcode.com/problems/remove-linked-list-elements/

JavaScript

/**
 * Definition for singly-linked list.
 * function ListNode(val) {
 *     this.val = val;
 *     this.next = null;
 * }
 */

/**
 * @param {ListNode} head
 * @param {number} val
 * @return {ListNode}
 */
var removeElements = function(head, val) {
    while (head && head.val === val) {
        head = head.next
    }
    let cur = head
    while (cur && cur.next) {
        if (cur.next.val === val) {
            cur.next = cur.next.next
        } else {
            cur = cur.next
        }
    }
    return head
}

Python

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None


class Solution:

    def removeElements(self, head, val):
        """
        :type head: ListNode
        :type val: int
        :rtype: ListNode
        """
        while head and head.val == val:
            head = head.next
        cur = head
        while cur and cur.next:
            if cur.next.val == val:
                cur.next = cur.next.next
            else:
                cur = cur.next
        return head