Map fn for Linked Lists

map-linked-list.js

// function Node(data, next = null) {
//   this.data = data;
//   this.next = next;
// }

function map(head, fn) {
  if (!head) return null; // Just return bad nodes
  
  const mappedHead = new Node(fn(head.data));
  let lastMappedNode = mappedHead;
  let currentNode = head.next;
  let currentMappedNode;
  
  while (currentNode) {
    // Create the new mapped node
    currentMappedNode = new Node(fn(currentNode.data));
    
    // Link the last node
    lastMappedNode.next = currentMappedNode;
    
    // Update the pointers
    currentNode = currentNode.next;
    lastMappedNode = currentMappedNode;
  }

  return mappedHead;
}

// const secondElem = Node('second');
// const head = Node('head', secondElement);

// Node.prototype.map = Node.prototype.map || map(this);

// map(head, elem => elem + 1);
// head.map(elem => elem + 1);

// const arr = [1, 2, 3];
// arr.map(elem => {
//   return elem + 1;
// });

// const reduceInputFunction = function (accumulator, currentValue, index, originalArray) {
// };
// arr.reduce(reduceInputFunction);

// const mapInputFunction = function (arrayElement, index, originalArray) {
//   return arrayElement + 1;
// };
// arr.map(mapInputFunction);

// arr.map(function (arrayElement) {
//   return arrayElement + 1;
// });

// arr.map(arrayElem => {
//   return arrayElement + 1;
// });

// arr.map(arrayElem => arrayElement + 1);