diff --git a/Algorithms/0016. 3Sum Closest/16. 3Sum Closest.go b/Algorithms/0016. 3Sum Closest/16. 3Sum Closest.go
index aa0c03bb..0c3db8eb 100644
--- a/Algorithms/0016. 3Sum Closest/16. 3Sum Closest.go	
+++ b/Algorithms/0016. 3Sum Closest/16. 3Sum Closest.go	
@@ -5,6 +5,7 @@ import (
 	"sort"
 )
 
+// 解法一 O(n^2)
 func threeSumClosest(nums []int, target int) int {
 	n, res, diff := len(nums), 0, math.MaxInt32
 	if n > 2 {
@@ -28,6 +29,7 @@ func threeSumClosest(nums []int, target int) int {
 	return res
 }
 
+// 解法二 暴力解法 O(n^3)
 func threeSumClosest_(nums []int, target int) int {
 	res, difference := 0, math.MaxInt16
 	for i := 0; i < len(nums); i++ {
diff --git a/Algorithms/0019. Remove Nth Node From End of List/19. Remove Nth Node From End of List.go b/Algorithms/0019. Remove Nth Node From End of List/19. Remove Nth Node From End of List.go
index 80ae7e27..5642bcc7 100644
--- a/Algorithms/0019. Remove Nth Node From End of List/19. Remove Nth Node From End of List.go	
+++ b/Algorithms/0019. Remove Nth Node From End of List/19. Remove Nth Node From End of List.go	
@@ -8,6 +8,7 @@ package leetcode
  * }
  */
 
+// 解法一
 func removeNthFromEnd(head *ListNode, n int) *ListNode {
 	var fast, slow *ListNode
 	fast = head
@@ -27,6 +28,7 @@ func removeNthFromEnd(head *ListNode, n int) *ListNode {
 	return head
 }
 
+// 解法二
 func removeNthFromEnd_(head *ListNode, n int) *ListNode {
 	if head == nil {
 		return nil
diff --git a/Algorithms/0026. Remove Duplicates from Sorted Array/26. Remove Duplicates from Sorted Array.go b/Algorithms/0026. Remove Duplicates from Sorted Array/26. Remove Duplicates from Sorted Array.go
index 7769c06e..8cdd3c02 100644
--- a/Algorithms/0026. Remove Duplicates from Sorted Array/26. Remove Duplicates from Sorted Array.go	
+++ b/Algorithms/0026. Remove Duplicates from Sorted Array/26. Remove Duplicates from Sorted Array.go	
@@ -1,5 +1,6 @@
 package leetcode
 
+// 解法一
 func removeDuplicates(nums []int) int {
 	if len(nums) == 0 {
 		return 0
@@ -18,6 +19,7 @@ func removeDuplicates(nums []int) int {
 	return last + 1
 }
 
+// 解法二
 func removeDuplicates_(nums []int) int {
 	if len(nums) == 0 {
 		return 0
diff --git a/Algorithms/0028. Implement strStr()/28. Implement strStr().go b/Algorithms/0028. Implement strStr()/28. Implement strStr().go
index b4db8b21..9b033e39 100644
--- a/Algorithms/0028. Implement strStr()/28. Implement strStr().go	
+++ b/Algorithms/0028. Implement strStr()/28. Implement strStr().go	
@@ -2,6 +2,7 @@ package leetcode
 
 import "strings"
 
+// 解法一
 func strStr(haystack string, needle string) int {
 	for i := 0; ; i++ {
 		for j := 0; ; j++ {
@@ -18,6 +19,7 @@ func strStr(haystack string, needle string) int {
 	}
 }
 
+// 解法二
 func strStr_(haystack string, needle string) int {
 	return strings.Index(haystack, needle)
 }
diff --git a/Algorithms/0086. Partition List/86. Partition List.go b/Algorithms/0086. Partition List/86. Partition List.go
index 9c72561a..58b745b9 100644
--- a/Algorithms/0086. Partition List/86. Partition List.go	
+++ b/Algorithms/0086. Partition List/86. Partition List.go	
@@ -7,6 +7,8 @@ package leetcode
  *     Next *ListNode
  * }
  */
+
+// 解法一 单链表
 func partition(head *ListNode, x int) *ListNode {
 	beforeHead := &ListNode{Val: 0, Next: nil}
 	before := beforeHead
@@ -34,6 +36,7 @@ type DoublyListNode struct {
 	Next *DoublyListNode
 }
 
+// 解法二 双链表
 func partition_(head *ListNode, x int) *ListNode {
 	if head == nil || head.Next == nil {
 		return head
diff --git a/Algorithms/0143. Reorder List/143. Reorder List.go b/Algorithms/0143. Reorder List/143. Reorder List.go
index 9fef7121..68a31c1b 100644
--- a/Algorithms/0143. Reorder List/143. Reorder List.go	
+++ b/Algorithms/0143. Reorder List/143. Reorder List.go	
@@ -7,6 +7,8 @@ package leetcode
  *     Next *ListNode
  * }
  */
+
+// 解法一 单链表
 func reorderList(head *ListNode) *ListNode {
 	if head == nil || head.Next == nil {
 		return head
@@ -43,6 +45,7 @@ func reorderList(head *ListNode) *ListNode {
 	return head
 }
 
+// 解法二 数组
 func reorderList_1(head *ListNode) *ListNode {
 	array := listToArray(head)
 	length := len(array)
diff --git a/Algorithms/0144. Binary Tree Preorder Traversal/144. Binary Tree Preorder Traversal.go b/Algorithms/0144. Binary Tree Preorder Traversal/144. Binary Tree Preorder Traversal.go
index a4bb7615..ba0cc501 100644
--- a/Algorithms/0144. Binary Tree Preorder Traversal/144. Binary Tree Preorder Traversal.go	
+++ b/Algorithms/0144. Binary Tree Preorder Traversal/144. Binary Tree Preorder Traversal.go	
@@ -8,6 +8,8 @@ package leetcode
  *     Right *TreeNode
  * }
  */
+
+// 解法一
 func preorderTraversal(root *TreeNode) []int {
 	res := []int{}
 	if root != nil {
@@ -24,6 +26,7 @@ func preorderTraversal(root *TreeNode) []int {
 	return res
 }
 
+// 解法二
 func preorderTraversal_(root *TreeNode) []int {
 	var result []int
 	preorder(root, &result)
diff --git a/Algorithms/0148. Sort List/README.md b/Algorithms/0148. Sort List/README.md
index d0b3383c..3153f7ef 100644
--- a/Algorithms/0148. Sort List/README.md	
+++ b/Algorithms/0148. Sort List/README.md	
@@ -24,4 +24,4 @@ Output: -1->0->3->4->5
 
 ## 解题思路
 
-这道题只能用归并排序才能符合要求。归并排序需要的 2 个操作在其他题目已经出现过了，取中间点，第 876 题，合并 2 个有序链表，第 21 题。
\ No newline at end of file
+这道题只能用归并排序才能符合要求。归并排序需要的 2 个操作在其他题目已经出现过了，取中间点是第 876 题，合并 2 个有序链表是第 21 题。
\ No newline at end of file
diff --git a/Algorithms/0164. Maximum Gap/164. Maximum Gap.go b/Algorithms/0164. Maximum Gap/164. Maximum Gap.go
index d1ac0420..ceac05de 100644
--- a/Algorithms/0164. Maximum Gap/164. Maximum Gap.go	
+++ b/Algorithms/0164. Maximum Gap/164. Maximum Gap.go	
@@ -1,5 +1,6 @@
 package leetcode
 
+// 解法一
 func maximumGap(nums []int) int {
 	if len(nums) < 2 {
 		return 0
@@ -36,6 +37,7 @@ func quickSort__(a []int, lo, hi int) {
 	quickSort__(a, p+1, hi)
 }
 
+// 解法二
 func maximumGap_(nums []int) int {
 
 	if nums == nil || len(nums) < 2 {
diff --git a/Algorithms/0167. Two Sum II - Input array is sorted/167. Two Sum II - Input array is sorted.go b/Algorithms/0167. Two Sum II - Input array is sorted/167. Two Sum II - Input array is sorted.go
index 5d80c074..17a289f8 100644
--- a/Algorithms/0167. Two Sum II - Input array is sorted/167. Two Sum II - Input array is sorted.go	
+++ b/Algorithms/0167. Two Sum II - Input array is sorted/167. Two Sum II - Input array is sorted.go	
@@ -1,6 +1,6 @@
 package leetcode
 
-// 这一题可以利用数组有序的特性
+// 解法一 这一题可以利用数组有序的特性
 func twoSum_(numbers []int, target int) []int {
 	i, j := 0, len(numbers)-1
 	for i < j {
@@ -15,7 +15,7 @@ func twoSum_(numbers []int, target int) []int {
 	return []int{-1, -1}
 }
 
-// 不管数组是否有序，空间复杂度比上一种解法要多 O(n)
+// 解法二 不管数组是否有序，空间复杂度比上一种解法要多 O(n)
 func twoSum__(numbers []int, target int) []int {
 	m := make(map[int]int)
 	for i := 0; i < len(numbers); i++ {
diff --git a/Algorithms/0215. Kth Largest Element in an Array/215. Kth Largest Element in an Array.go b/Algorithms/0215. Kth Largest Element in an Array/215. Kth Largest Element in an Array.go
index ff19b908..236dc5eb 100644
--- a/Algorithms/0215. Kth Largest Element in an Array/215. Kth Largest Element in an Array.go	
+++ b/Algorithms/0215. Kth Largest Element in an Array/215. Kth Largest Element in an Array.go	
@@ -2,13 +2,13 @@ package leetcode
 
 import "sort"
 
-// 排序的方法反而速度是最快的
+// 解法一 排序，排序的方法反而速度是最快的
 func findKthLargest_(nums []int, k int) int {
 	sort.Ints(nums)
 	return nums[len(nums)-k]
 }
 
-// 这个方法的理论依据是 partition 得到的点的下标就是最终排序之后的下标，根据这个下标，我们可以判断第 K 大的数在哪里
+// 解法二 这个方法的理论依据是 partition 得到的点的下标就是最终排序之后的下标，根据这个下标，我们可以判断第 K 大的数在哪里
 func findKthLargest(nums []int, k int) int {
 	if len(nums) == 0 {
 		return 0
diff --git a/Algorithms/0242. Valid Anagram/242. Valid Anagram.go b/Algorithms/0242. Valid Anagram/242. Valid Anagram.go
index b16b09e9..0531f39c 100644
--- a/Algorithms/0242. Valid Anagram/242. Valid Anagram.go	
+++ b/Algorithms/0242. Valid Anagram/242. Valid Anagram.go	
@@ -1,5 +1,6 @@
 package leetcode
 
+// 解法一
 func isAnagram(s string, t string) bool {
 	alphabet := make([]int, 26)
 	sBytes := []byte(s)
@@ -20,6 +21,8 @@ func isAnagram(s string, t string) bool {
 	}
 	return true
 }
+
+// 解法二
 func isAnagram_(s string, t string) bool {
 	if s == "" && t == "" {
 		return true
diff --git a/Algorithms/0274. H-Index/274. H-Index.go b/Algorithms/0274. H-Index/274. H-Index.go
index c29de8dd..35e59317 100644
--- a/Algorithms/0274. H-Index/274. H-Index.go	
+++ b/Algorithms/0274. H-Index/274. H-Index.go	
@@ -22,7 +22,7 @@ func hIndex(citations []int) int {
 }
 
 // 解法二
-func hIndex__(citations []int) int {
+func hIndex_(citations []int) int {
 	quickSort__(citations, 0, len(citations)-1)
 	hIndex := 0
 	for i := len(citations) - 1; i >= 0; i-- {
diff --git a/Algorithms/0287. Find the Duplicate Number/287. Find the Duplicate Number.go b/Algorithms/0287. Find the Duplicate Number/287. Find the Duplicate Number.go
index 00a7b14f..d7cdb98e 100644
--- a/Algorithms/0287. Find the Duplicate Number/287. Find the Duplicate Number.go	
+++ b/Algorithms/0287. Find the Duplicate Number/287. Find the Duplicate Number.go	
@@ -2,6 +2,7 @@ package leetcode
 
 import "sort"
 
+// 解法一
 func findDuplicate(nums []int) int {
 	slow := nums[0]
 	fast := nums[nums[0]]
@@ -17,6 +18,7 @@ func findDuplicate(nums []int) int {
 	return walker
 }
 
+// 解法二
 func findDuplicate_(nums []int) int {
 	if len(nums) == 0 {
 		return 0
diff --git a/Algorithms/0324. Wiggle Sort II/324. Wiggle Sort II.go b/Algorithms/0324. Wiggle Sort II/324. Wiggle Sort II.go
index 9093e661..c0c3dc85 100644
--- a/Algorithms/0324. Wiggle Sort II/324. Wiggle Sort II.go	
+++ b/Algorithms/0324. Wiggle Sort II/324. Wiggle Sort II.go	
@@ -4,6 +4,7 @@ import (
 	"sort"
 )
 
+// 解法一
 func wiggleSort(nums []int) {
 	if len(nums) < 2 {
 		return
@@ -64,6 +65,7 @@ func partition__324(a []int, lo, hi int) int {
 	return i + 1
 }
 
+// 解法二
 func wiggleSort_(nums []int) {
 	if len(nums) < 2 {
 		return
diff --git a/Algorithms/0725. Split Linked List in Parts/725. Split Linked List in Parts_test.go b/Algorithms/0725. Split Linked List in Parts/725. Split Linked List in Parts_test.go
index a27c893f..433086fa 100644
--- a/Algorithms/0725. Split Linked List in Parts/725. Split Linked List in Parts_test.go	
+++ b/Algorithms/0725. Split Linked List in Parts/725. Split Linked List in Parts_test.go	
@@ -47,30 +47,30 @@ func Test_Problem725(t *testing.T) {
 			ans725{[]int{}},
 		},
 
-		// question725{
-		// 	para725{[]int{1, 2, 3, 2, 3, 2, 3, 2}, 0},
-		// 	ans725{[]int{1, 2, 3, 2, 3, 2, 3, 2}},
-		// },
+		question725{
+			para725{[]int{1, 2, 3, 2, 3, 2, 3, 2}, 0},
+			ans725{[]int{1, 2, 3, 2, 3, 2, 3, 2}},
+		},
 
-		// question725{
-		// 	para725{[]int{1, 2, 3, 4, 5}, 5},
-		// 	ans725{[]int{1, 2, 3, 4}},
-		// },
+		question725{
+			para725{[]int{1, 2, 3, 4, 5}, 5},
+			ans725{[]int{1, 2, 3, 4}},
+		},
 
-		// question725{
-		// 	para725{[]int{}, 5},
-		// 	ans725{[]int{}},
-		// },
+		question725{
+			para725{[]int{}, 5},
+			ans725{[]int{}},
+		},
 
-		// question725{
-		// 	para725{[]int{1, 2, 3, 4, 5}, 10},
-		// 	ans725{[]int{1, 2, 3, 4, 5}},
-		// },
+		question725{
+			para725{[]int{1, 2, 3, 4, 5}, 10},
+			ans725{[]int{1, 2, 3, 4, 5}},
+		},
 
-		// question725{
-		// 	para725{[]int{1}, 1},
-		// 	ans725{[]int{}},
-		// },
+		question725{
+			para725{[]int{1}, 1},
+			ans725{[]int{}},
+		},
 	}
 
 	fmt.Printf("------------------------Leetcode Problem 725------------------------\n")
diff --git a/Algorithms/0977. Squares of a Sorted Array/977. Squares of a Sorted Array.go b/Algorithms/0977. Squares of a Sorted Array/977. Squares of a Sorted Array.go
index fef98c97..215fee71 100644
--- a/Algorithms/0977. Squares of a Sorted Array/977. Squares of a Sorted Array.go	
+++ b/Algorithms/0977. Squares of a Sorted Array/977. Squares of a Sorted Array.go	
@@ -2,6 +2,7 @@ package leetcode
 
 import "sort"
 
+// 解法一
 func sortedSquares(A []int) []int {
 	ans := make([]int, len(A))
 	for i, k, j := 0, len(A)-1, len(ans)-1; i <= j; k-- {
@@ -16,6 +17,7 @@ func sortedSquares(A []int) []int {
 	return ans
 }
 
+// 解法二
 func sortedSquares_(A []int) []int {
 	for i, value := range A {
 		A[i] = value * value
diff --git a/Algorithms/1021. Remove Outermost Parentheses/1021. Remove Outermost Parentheses.go b/Algorithms/1021. Remove Outermost Parentheses/1021. Remove Outermost Parentheses.go
index 919904ec..76ea277a 100644
--- a/Algorithms/1021. Remove Outermost Parentheses/1021. Remove Outermost Parentheses.go	
+++ b/Algorithms/1021. Remove Outermost Parentheses/1021. Remove Outermost Parentheses.go	
@@ -1,7 +1,7 @@
 package leetcode
 
+// 解法一
 func removeOuterParentheses(S string) string {
-
 	now, current, ans := 0, "", ""
 	for _, char := range S {
 		if string(char) == "(" {
@@ -18,6 +18,7 @@ func removeOuterParentheses(S string) string {
 	return ans
 }
 
+// 解法二
 func removeOuterParentheses_(S string) string {
 	stack, res, counter := []byte{}, "", 0
 	for i := 0; i < len(S); i++ {