lcxdi8887个人战拖

之前发错地方了，转自

https://www.1point3acres.com/bbs/thread-573529-1-1.html

未来在这里更新

2020.01.11
LC2 Add 2 nums
更简洁的答案

1. var addTwoNumbers = function(l1, l2) {
   
2.     let n = new ListNode(0);
   
3.     let root = n;
   
4.     let carry = 0;
   
5.     while (l1 || l2 || carry) {
   
6.         let x1 = 0, x2 = 0;
   
7.         if (l1)  {
   
8.             x1 = l1.val;
   
9.             l1 = l1.next;
   
10.         }
    
11.         if (l2)  {
    
12.             x2 = l2.val;
    
13.             l2 = l2.next;
    
14.         }
    
15.         let all = x1 + x2 + carry;
    
16.         carry = parseInt(all/10);
    
17.         n.next = new ListNode(all%10);
    
18.         n = n.next;
    
19.     }
    
20.     return root.next;
    
21. };

复制代码

还有递归的写法可以尝试一下
还有一种思路是不使用新的链表，直接把结果保存到l1或者l2中来节省Space
注意时间复杂度是O(max(l1, l2))

2020.01.29
LC142 Cycle List II
按照答案思路写，但是不正确，因为太sb了，getIntersect里面while应该判断runner && runner.next，我写成!runner && !runner.next了。。。。https://leetcode-cn.com/submissions/detail/44778249/
Solutions
https://leetcode-cn.com/problems ... iao-ii-by-leetcode/

2020.02.02
这段比较忙，来不及做题，感觉休息一段以后就有点丢失了思考的感觉和做题的感觉
所以先来几道easy的找回一下感觉
LC21 Merge two lists
Solution1 one pass with extra space
提交三次，每次的耗时差别都比较大

LC1304 和为0的n个数数组
Easy, array
Solution1 生成成对和为0的数
Solution2
https://leetcode-cn.com/problems ... ng-shu-by-leetcode/

LC1299 每个元素替换为右侧最大的
Easy, array
Solution1 brute force
Solution2 (still thinking)

2020.01.12
LC19 Remove last n-th node
Solution1 with array
Solution2 with count
https://leetcode-cn.com/problems ... -nge-jie-dian-by-l/

2020.01.12
LC24 swap pairs
Solution1 通过基准点和下一对来处理
递归的解法可以尝试一下
https://leetcode-cn.com/problems ... iao-huan-lian-biao/

一开始的实现还是有问题，画图有助于理清思路

2020.01.13
LC61 Shift linked list
Solution1 先算length再shift
尝试形成环链再断开
https://leetcode-cn.com/problems ... n-biao-by-leetcode/

2020.01.20
LC6 ZigZag

2020.01.21
LC86 Partition List
https://leetcode-cn.com/problems ... n-biao-by-leetcode/

2020.01.22
LC9 Reverse List II
Solution1使用数组实现了
尝试使用三指针实现，有些题的最佳答案和我的想法一样，尽量先尝试再看答案
https://leetcode-cn.com/problems ... iao-ii-by-leetcode/