Update 0019、0066

Author: halfrost

leetcode/0019.Remove-Nth-Node-From-End-of-List/README.md

@@ -2,16 +2,44 @@
 
 ## 题目
 
-Given a linked list, remove the n-th node from the end of list and return its head.
+Given the `head` of a linked list, remove the `nth` node from the end of the list and return its head.
 
-Example:
+**Follow up:** Could you do this in one pass?
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2020/10/03/remove_ex1.jpg)
+
+```
+Input: head = [1,2,3,4,5], n = 2
+Output: [1,2,3,5]
 
 ```
-Given linked list: 1->2->3->4->5, and n = 2.
 
-After removing the second node from the end, the linked list becomes 1->2->3->5.
+**Example 2:**
+
+```
+Input: head = [1], n = 1
+Output: []
+
 ```
 
+**Example 3:**
+
+```
+Input: head = [1,2], n = 1
+Output: [1]
+
+```
+
+**Constraints:**
+
+- The number of nodes in the list is `sz`.
+- `1 <= sz <= 30`
+- `0 <= Node.val <= 100`
+- `1 <= n <= sz`
+
+
 ## 题目大意
 
 删除链表中倒数第 n 个结点。

website/content/ChapterFour/0001~0099/0019.Remove-Nth-Node-From-End-of-List.md

@@ -2,18 +2,43 @@
 
 ## 题目
 
-Given a linked list, remove the n-th node from the end of list and return its head.
+Given the `head` of a linked list, remove the `nth` node from the end of the list and return its head.
 
-**Example**:
+**Follow up:** Could you do this in one pass?
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2020/10/03/remove_ex1.jpg)
+
+```
+Input: head = [1,2,3,4,5], n = 2
+Output: [1,2,3,5]
+
+```
+
+**Example 2:**
+
+```
+Input: head = [1], n = 1
+Output: []
 
 ```
 
-Given linked list: 1->2->3->4->5, and n = 2.
+**Example 3:**
 
-After removing the second node from the end, the linked list becomes 1->2->3->5.
+```
+Input: head = [1,2], n = 1
+Output: [1]
 
 ```
 
+**Constraints:**
+
+- The number of nodes in the list is `sz`.
+- `1 <= sz <= 30`
+- `0 <= Node.val <= 100`
+- `1 <= n <= sz`
+
 ## 题目大意
 
 删除链表中倒数第 n 个结点。
@@ -30,6 +55,13 @@ After removing the second node from the end, the linked list becomes 1->2->3->5.
 
 package leetcode
 
+import (
+	"github.com/halfrost/LeetCode-Go/structures"
+)
+
+// ListNode define
+type ListNode = structures.ListNode
+
 /**
  * Definition for singly-linked list.
  * type ListNode struct {
@@ -40,13 +72,16 @@ package leetcode
 
 // 解法一
 func removeNthFromEnd(head *ListNode, n int) *ListNode {
+	if head == nil {
+		return nil
+	}
 	var fast, slow *ListNode
 	fast = head
 	slow = head
 	step := 0
 	for i := 0; i < n; i++ {
 		// n maybe much larger than length of linklist
-		if fast.Next == nil && step != 0 && step < n-1 {
+		if fast.Next == nil && step < n-1 {
 			return head
 		}
 		fast = fast.Next
@@ -103,6 +138,7 @@ func removeNthFromEnd1(head *ListNode, n int) *ListNode {
 }
 
 
+
 ```
 
 

website/content/ChapterFour/0001~0099/0066.Plus-One.md

@@ -41,27 +41,23 @@ You may assume the integer does not contain any leading zero, except the number
 package leetcode
 
 func plusOne(digits []int) []int {
-	if len(digits) == 0 {
-		return []int{}
-	}
-	carry := 1
 	for i := len(digits) - 1; i >= 0; i-- {
-		if digits[i]+carry > 9 {
-			digits[i] = 0
-			carry = 1
-		} else {
-			digits[i] += carry
-			carry = 0
-			break
+		digits[i]++
+		if digits[i] != 10 {
+			// no carry
+			return digits
 		}
+		// carry
+		digits[i] = 0
 	}
-	if digits[0] == 0 && carry == 1 {
-		digits = append([]int{1}, digits...)
-	}
+	// all carry
+	digits[0] = 1
+	digits = append(digits, 0)
 	return digits
 }
 
 
+
 ```