diff --git a/README.md b/README.md
index 6027885d..e3b35581 100644
--- a/README.md
+++ b/README.md
@@ -753,9 +753,9 @@
 
 | Title | Solution | Difficulty | Time | Space |收藏| 
 | ----- | -------- | ---------- | ---- | ----- | ----- |
-[2. Add Two Numbers](https://leetcode.com/problems/add-two-numbers)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/2.Add-Two-Number)| Medium | O(n)| O(1)||
-[19. Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/19.Remove%20Nth%20Node%20From%20End%20of%20List)| Medium | O(n)| O(1)||
-[21. Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/21.Merge%20Two%20Sorted%20Lists)| Easy | O(log n)| O(1)||
+[2. Add Two Numbers](https://leetcode.com/problems/add-two-numbers)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/0002.%20Add-Two-Number)| Medium | O(n)| O(1)||
+[19. Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/0019.%20Remove%20Nth%20Node%20From%20End%20of%20List)| Medium | O(n)| O(1)||
+[21. Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/0021.%20Merge%20Two%20Sorted%20Lists)| Easy | O(log n)| O(1)||
 [23. Merge k Sorted Lists](https://leetcode.com/problems/merge-k-sorted-lists/)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/23.Merge%20k%20Sorted%20Lists)| Hard | O(log n)| O(1)|❤️|
 [24. Swap Nodes in Pairs](https://leetcode.com/problems/swap-nodes-in-pairs/)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/24.Swap-Nodes-in-Pairs)| Medium | O(n)| O(1)||
 [25. Reverse Nodes in k-Group](https://leetcode.com/problems/reverse-nodes-in-k-group/)| [Go](https://github.com/halfrost/LeetCode-Go/tree/master/Algorithms/25.Reverse%20Nodes%20in%20k%20Group)| Hard | O(log n)| O(1)|❤️|