From f2a1ad632f99c6f1a37ab4b88310e2c03f7a8c52 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=B2=89=E9=BB=98?=
 <71065161+chenmo1995@users.noreply.github.com>
Date: Thu, 30 Dec 2021 14:32:20 +0800
Subject: [PATCH 1/7] =?UTF-8?q?Update=200222.=E5=AE=8C=E5=85=A8=E4=BA=8C?=
 =?UTF-8?q?=E5=8F=89=E6=A0=91=E7=9A=84=E8=8A=82=E7=82=B9=E4=B8=AA=E6=95=B0?=
 =?UTF-8?q?.md?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0222.完全二叉树的节点个数.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/problems/0222.完全二叉树的节点个数.md b/problems/0222.完全二叉树的节点个数.md
index c5039039..754a6094 100644
--- a/problems/0222.完全二叉树的节点个数.md
+++ b/problems/0222.完全二叉树的节点个数.md
@@ -80,7 +80,7 @@ return treeNum;
 class Solution {
 private:
     int getNodesNum(TreeNode* cur) {
-        if (cur == 0) return 0;
+        if (cur == NULL) return 0;
         int leftNum = getNodesNum(cur->left);      // 左
         int rightNum = getNodesNum(cur->right);    // 右
         int treeNum = leftNum + rightNum + 1;      // 中

From 4ed7da80c08a51cc79cbc0aa987d41f6a57da5fe Mon Sep 17 00:00:00 2001
From: Steve <841532108@qq.com>
Date: Fri, 31 Dec 2021 16:18:03 +0800
Subject: [PATCH 2/7] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200704.=E4=BA=8C?=
 =?UTF-8?q?=E5=88=86=E6=9F=A5=E6=89=BE.md=20Typescript=20=E7=89=88?=
 =?UTF-8?q?=E6=9C=AC?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0704.二分查找.md | 40 +++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/problems/0704.二分查找.md b/problems/0704.二分查找.md
index 689c0633..cc7d7de5 100644
--- a/problems/0704.二分查找.md
+++ b/problems/0704.二分查找.md
@@ -326,6 +326,46 @@ var search = function(nums, target) {
 };
 ```
 
+**TypeScript**
+
+（版本一）左闭右闭区间
+
+```typescript
+function search(nums: number[], target: number): number {
+    let left: number = 0, right: number = nums.length - 1;
+    while (left <= right) {
+        let mid: number = left + Math.floor((right - left) / 2);
+        if (nums[mid] > target) {
+            right = mid - 1;
+        } else if (nums[mid] < target) {
+            left = mid + 1;
+        } else {
+            return mid;
+        }
+    }
+    return -1;
+};
+```
+
+（版本二）左闭右开区间
+
+```typescript
+function search(nums: number[], target: number): number {
+    let left: number = 0, right: number = nums.length;
+    while (left < right) {
+        let mid: number = left + Math.floor((right - left) / 2);
+        if (nums[mid] > target) {
+            right = mid;
+        } else if (nums[mid] < target) {
+            left = mid + 1;
+        } else {
+            return mid;
+        }
+    }
+    return -1;
+};
+```
+
 **Ruby:**
 
 ```ruby

From 0dbd6c42d249cf0a33bdcd9a2f67c023f83003f1 Mon Sep 17 00:00:00 2001
From: Steve <841532108@qq.com>
Date: Fri, 31 Dec 2021 16:29:05 +0800
Subject: [PATCH 3/7] =?UTF-8?q?=E6=9B=B4=E6=96=B0=200704.=E4=BA=8C?=
 =?UTF-8?q?=E5=88=86=E6=9F=A5=E6=89=BE.md=EF=BC=9A=E5=88=A0=E9=99=A4?=
 =?UTF-8?q?=E5=A4=9A=E4=BD=99=E5=AD=97=E7=AC=A6=EF=BC=8C=E5=AF=BC=E8=87=B4?=
 =?UTF-8?q?=E4=BB=A3=E7=A0=81=E6=9C=AA=E9=AB=98=E4=BA=AE?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0704.二分查找.md | 1 -
 1 file changed, 1 deletion(-)

diff --git a/problems/0704.二分查找.md b/problems/0704.二分查找.md
index cc7d7de5..379cb5fc 100644
--- a/problems/0704.二分查找.md
+++ b/problems/0704.二分查找.md
@@ -284,7 +284,6 @@ func search(nums []int, target int) int {
  * @param {number} target
  * @return {number}
  */
-/**
 var search = function(nums, target) {
     let left = 0, right = nums.length - 1;
     // 使用左闭右闭区间

From d58fe4ea60f314dd4a9ffdd41beadc4710369ba7 Mon Sep 17 00:00:00 2001
From: Kai Dang <15596570256@163.com>
Date: Fri, 31 Dec 2021 17:04:46 +0800
Subject: [PATCH 4/7] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200040.=E7=BB=84?=
 =?UTF-8?q?=E5=90=88=E6=80=BB=E5=92=8CII.md=20=E4=B8=AD=E7=9A=84Java?=
 =?UTF-8?q?=E4=B8=8EGo=E7=9A=84=E4=B8=8D=E4=BD=BF=E7=94=A8=E6=A0=87?=
 =?UTF-8?q?=E8=AE=B0=E6=95=B0=E7=BB=84=E7=9A=84=E8=A7=A3=E6=B3=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0040.组合总和II.md | 76 ++++++++++++++++++++++++++++++++-
 1 file changed, 75 insertions(+), 1 deletion(-)

diff --git a/problems/0040.组合总和II.md b/problems/0040.组合总和II.md
index 31011ed6..5d9e4965 100644
--- a/problems/0040.组合总和II.md
+++ b/problems/0040.组合总和II.md
@@ -255,6 +255,7 @@ public:
 
 
 ## Java 
+**使用标记数组**
 ```Java
 class Solution {
     List<List<Integer>> lists = new ArrayList<>();
@@ -292,6 +293,44 @@ class Solution {
     }
 }
 ```
+**不使用标记数组**
+```Java
+class Solution {
+  List<List<Integer>> res = new ArrayList<>();
+  LinkedList<Integer> path = new LinkedList<>();
+  int sum = 0;
+  
+  public List<List<Integer>> combinationSum2( int[] candidates, int target ) {
+    //为了将重复的数字都放到一起，所以先进行排序
+    Arrays.sort( candidates );
+    backTracking( candidates, target, 0 );
+    return res;
+  }
+  
+  private void backTracking( int[] candidates, int target, int start ) {
+    if ( sum == target ) {
+      res.add( new ArrayList<>( path ) );
+      return;
+    }
+    for ( int i = start; i < candidates.length && sum + candidates[i] <= target; i++ ) {
+      //正确剔除重复解的办法
+      //跳过同一树层使用过的元素
+      if ( i > start && candidates[i] == candidates[i - 1] ) {
+        continue;
+      }
+
+      sum += candidates[i];
+      path.add( candidates[i] );
+      // i+1 代表当前组内元素只选取一次
+      backTracking( candidates, target, i + 1 );
+
+      int temp = path.getLast();
+      sum -= temp;
+      path.removeLast();
+    }
+  }
+}
+```
 
 ## Python 
 **回溯+巧妙去重(省去使用used**
@@ -384,6 +423,7 @@ class Solution:
 ## Go
 主要在于如何在回溯中去重
 
+**使用used数组**
 ```go
 func combinationSum2(candidates []int, target int) [][]int {
     var trcak []int
@@ -423,7 +463,41 @@ func backtracking(startIndex,sum,target int,candidates,trcak []int,res *[][]int,
     }
 }
 ```
-
+**不使用used数组**
+```go
+func combinationSum2(candidates []int, target int) [][]int {
+    var trcak []int
+    var res [][]int
+    sort.Ints(candidates)
+    backtracking(0,0,target,candidates,trcak,&res)
+    return res
+}
+func backtracking(startIndex,sum,target int,candidates,trcak []int,res *[][]int){
+    //终止条件
+    if sum==target{
+        tmp:=make([]int,len(trcak))
+        //拷贝
+        copy(tmp,trcak)
+        //放入结果集
+        *res=append(*res,tmp)
+        return
+    }
+    //回溯
+    for i:=startIndex;i<len(candidates) && sum+candidates[i]<=target;i++{
+        // 若当前树层有使用过相同的元素，则跳过
+        if i>startIndex&&candidates[i]==candidates[i-1]{
+                continue
+        }
+        //更新路径集合和sum
+        trcak=append(trcak,candidates[i])
+        sum+=candidates[i]
+        backtracking(i+1,sum,target,candidates,trcak,res)
+        //回溯
+        trcak=trcak[:len(trcak)-1]
+        sum-=candidates[i]
+    }
+}
+```
 ## javaScript
 
 ```js

From 46ceb72cd01b08f6a734ca87d329c56ec51a51e6 Mon Sep 17 00:00:00 2001
From: erdengk <15596570256@163.com>
Date: Sun, 2 Jan 2022 11:21:56 +0800
Subject: [PATCH 5/7] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200090.=E5=AD=90?=
 =?UTF-8?q?=E9=9B=86II.md=20=E4=B8=AD=E7=9A=84Java=E4=B8=8D=E4=BD=BF?=
 =?UTF-8?q?=E7=94=A8=E6=A0=87=E8=AE=B0=E6=95=B0=E7=BB=84=E7=9A=84=E8=A7=A3?=
 =?UTF-8?q?=E6=B3=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0090.子集II.md | 33 ++++++++++++++++++++++++++++++++-
 1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/problems/0090.子集II.md b/problems/0090.子集II.md
index 5b92517a..a1e86464 100644
--- a/problems/0090.子集II.md
+++ b/problems/0090.子集II.md
@@ -166,7 +166,7 @@ if (i > startIndex && nums[i] == nums[i - 1] ) {
 
 
 ### Java  
-
+使用used数组
 ```java
 class Solution {
    List<List<Integer>> result = new ArrayList<>();// 存放符合条件结果的集合
@@ -202,6 +202,37 @@ class Solution {
 }
 ```
 
+不使用used数组
+```java
+class Solution {
+
+  List<List<Integer>> res = new ArrayList<>();
+  LinkedList<Integer> path = new LinkedList<>();
+  
+  public List<List<Integer>> subsetsWithDup( int[] nums ) {
+    Arrays.sort( nums );
+    subsetsWithDupHelper( nums, 0 );
+    return res;
+  }
+
+
+  private void subsetsWithDupHelper( int[] nums, int start ) {
+    res.add( new ArrayList<>( path ) );
+
+    for ( int i = start; i < nums.length; i++ ) {
+        // 跳过当前树层使用过的、相同的元素
+      if ( i > start && nums[i - 1] == nums[i] ) {
+        continue;
+      }
+      path.add( nums[i] );
+      subsetsWithDupHelper( nums, i + 1 );
+      path.removeLast();
+    }
+  }
+
+}
+```
+
 ### Python 
 ```python
 class Solution:

From 9a1788dbf829500890da8b0c0de512f3260ce157 Mon Sep 17 00:00:00 2001
From: youngyangyang04 <826123027@qq.com>
Date: Wed, 5 Jan 2022 19:49:07 +0800
Subject: [PATCH 6/7] Update

---
 README.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 5121dd29..55f1356a 100644
--- a/README.md
+++ b/README.md
@@ -4,9 +4,9 @@
 👉 推荐 [Gitee同步](https://gitee.com/programmercarl/leetcode-master) 
 
 > 1. **介绍**：本项目是一套完整的刷题计划，旨在帮助大家少走弯路，循序渐进学算法，[关注作者](#关于作者)
-> 2. **PDF版本** ： [「代码随想录」算法精讲 PDF 版本](https://mp.weixin.qq.com/s/NF7NqTD9DU505S6nvR_5Wg) 。
+> 2. **PDF版本** ： [「代码随想录」算法精讲 PDF 版本](https://programmercarl.com/other/algo_pdf.html) 。
 > 3. **刷题顺序** ： README已经将刷题顺序排好了，按照顺序一道一道刷就可以。
-> 4. **学习社区** : 一起学习打卡/面试技巧/如何选择offer/大厂内推/职场规则/简历修改/技术分享/程序人生。欢迎加入[「代码随想录」知识星球](https://mp.weixin.qq.com/s/QVF6upVMSbgvZy8lHZS3CQ) 。
+> 4. **学习社区** : 一起学习打卡/面试技巧/如何选择offer/大厂内推/职场规则/简历修改/技术分享/程序人生。欢迎加入[「代码随想录」知识星球](https://programmercarl.com/other/kstar.html) 。
 > 5. **提交代码**：本项目统一使用C++语言进行讲解，但已经有Java、Python、Go、JavaScript等等多语言版本，感谢[这里的每一位贡献者](https://github.com/youngyangyang04/leetcode-master/graphs/contributors)，如果你也想贡献代码点亮你的头像，[点击这里](https://mp.weixin.qq.com/s/tqCxrMEU-ajQumL1i8im9A)了解提交代码的方式。
 > 6. **转载须知** ：以下所有文章皆为我（[程序员Carl](https://github.com/youngyangyang04)）的原创。引用本项目文章请注明出处，发现恶意抄袭或搬运，会动用法律武器维护自己的权益。让我们一起维护一个良好的技术创作环境！
 

From ab268238621421ec8c117b80f5ae812b1c1f783f Mon Sep 17 00:00:00 2001
From: youngyangyang04 <826123027@qq.com>
Date: Wed, 5 Jan 2022 20:02:16 +0800
Subject: [PATCH 7/7] Update

---
 README.md | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/README.md b/README.md
index 55f1356a..c5149776 100644
--- a/README.md
+++ b/README.md
@@ -564,14 +564,14 @@
 
 # 关于作者
 
-大家好，我是程序员Carl，哈工大师兄，ACM 校赛、黑龙江省赛、东北四省赛金牌、亚洲区域赛铜牌获得者，先后在腾讯和百度从事后端技术研发，CSDN博客专家。对算法和C++后端技术有一定的见解，利用工作之余重新刷leetcode。 
+大家好，我是程序员Carl，哈工大师兄，《代码随想录》作者，先后在腾讯和百度从事后端技术研发，CSDN博客专家。对算法和C++后端技术有一定的见解，利用工作之余重新刷leetcode。 
 
-加入刷题微信群，备注：「个人简单介绍」 + 组队刷题
+加入「代码随想录」刷题小分队（微信群），可以扫下方二维码加我微信。
 
-也欢迎与我交流，备注：「个人简单介绍」 + 交流，围观朋友圈，做点赞之交（备注没有自我介绍不通过哦）
+如果是已工作，备注：姓名-城市-岗位-组队刷题。如果学生，备注：姓名-学校-年级-组队刷题。**备注没有自我介绍不通过哦**
+
+<div align="center"><img src="https://code-thinking-1253855093.file.myqcloud.com/pics/20220102204804.png" data-img="1" width="200" height="200"></img></div>
 
-<a name="微信"></a>
-<div align="center"><img src="https://code-thinking-1253855093.file.myqcloud.com/pics/20211230153955.png" data-img="1" width="200" height="200"></img></div>
 
 
 # 公众号
@@ -585,10 +585,3 @@
 <a name="公众号"></a>
 <div align="center"><img src="https://code-thinking-1253855093.file.myqcloud.com/pics/20211026122841.png" data-img="1" width="650" height="500"></img></div>
 
-# 服务器 
-
-<p align="center"><strong>阿里云服务器，双11特价活动🔥🔥🔥🔥</p>
-<p align="center">
-<a href="https://www.aliyun.com/minisite/goods?taskPkg=1111ydsrwb&pkgSid=1959&recordId=962642&userCode=roof0wob" target="_blank">
-	<img src="./pics/阿里云.png" width="1000"/>
-</a>