148. 排序链表🔖链表🔖js初始化单链表

148. 排序链表

• https://leetcode-cn.com/problems/sort-list/

/**
 * Definition for singly-linked list.
 * function ListNode(val, next) {
 *     this.val = (val===undefined ? 0 : val)
 *     this.next = (next===undefined ? null : next)
 * }
 */
/**
 * @param {ListNode} head
 * @return {ListNode}
 */
var sortList = function (head) {
  if (head === null) return head;
  let arr = [];
  while (head !== null) {
    arr.push(head.val);
    head = head.next;
  }
  let result = arr.sort((a, b) => {
    return a - b;
  });
  let result_head = new ListNode(result[0], null);
  let test = result_head;
  result.forEach((data, index) => {
    if (index !== 0) {
      let temp = new ListNode(data, null);
      test.next = temp;
      test = temp;
    }
  });
  return result_head;
};

js 初始化单链表

// 节点
class Node {
  constructor(value) {
    this.val = value;
    this.next = null;
  }
}

// 利用数组来初始化单链表
class NodeList {
  constructor(arr) {
    let head = new Node(arr.shift());
    let next = head;
    arr.forEach((data) => {
      next.next = new Node(data);
      next = next.next;
    });
    return head;
  }
}

let test = new NodeList([1, 2, 3, 4]);
while (test !== null) {
  console.log(test.val);
  test = test.next;
}