Code Signal: removeKFromList solution -- Interview Practice__Linked List - 01 (Easy)

removeKFromList.js

// Singly-linked lists are already defined with this interface:
// function ListNode(x) {
//   this.value = x;
//   this.next = null;
// }
//
function solution(l, k) {
    if (l === null) return l;       // return if the linked list is empty
    
    let dummyNode = new ListNode(); // create a dummy node whose next points to the head of the given Linked List
    dummyNode.next = l;
  
    let curr = l, prev = dummyNode; // set up two pointers to track the current node and the previous node
    
    while (curr) {                  // loop through the Linked List
        if (curr.value === k) {     // if the value of the node matches 'k'
            prev.next = curr.next;  // delete the node from the Linked List
        } else {                    // else
            prev = curr;            // move the previous pointer forward
        }
        curr = curr.next;           // move the current pointer forward
    }
    return dummyNode.next;          // return the head of the new Linked List
}