From f8004f9b41bc011f8e961f3065dbab61f1f63a7d Mon Sep 17 00:00:00 2001 From: simonhancrew <597494370@qq.com> Date: Thu, 27 May 2021 15:58:22 +0800 Subject: [PATCH 01/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200977.=E6=9C=89?= =?UTF-8?q?=E5=BA=8F=E6=95=B0=E7=BB=84=E7=9A=84=E5=B9=B3=E6=96=B9=20Python?= =?UTF-8?q?3=20Go=20Rust=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0977.有序数组的平方.md | 60 +++++++++++++++++++++++++- 1 file changed, 58 insertions(+), 2 deletions(-) diff --git a/problems/0977.有序数组的平方.md b/problems/0977.有序数组的平方.md index 167a258c..b5d392e6 100644 --- a/problems/0977.有序数组的平方.md +++ b/problems/0977.有序数组的平方.md @@ -100,10 +100,66 @@ public: Java： Python： - +```Python +class Solution: + def sortedSquares(self, nums: List[int]) -> List[int]: + n = len(nums) + i,j,k = 0,n - 1,n - 1 + ans = [-1] * n + while i <= j: + lm = nums[i] ** 2 + rm = nums[j] ** 2 + if lm > rm: + ans[k] = lm + i += 1 + else: + ans[k] = rm + j -= 1 + k -= 1 + return ans +``` Go： - +```Go +func sortedSquares(nums []int) []int { + n := len(nums) + i, j, k := 0, n-1, n-1 + ans := make([]int, n) + for i <= j { + lm, rm := nums[i]*nums[i], nums[j]*nums[j] + if lm > rm { + ans[k] = lm + i++ + } else { + ans[k] = rm + j-- + } + k-- + } + return ans +} +``` +Rust +``` +impl Solution { + pub fn sorted_squares(nums: Vec) -> Vec { + let n = nums.len(); + let (mut i,mut j,mut k) = (0,n - 1,n- 1); + let mut ans = vec![0;n]; + while i <= j{ + if nums[i] * nums[i] < nums[j] * nums[j] { + ans[k] = nums[j] * nums[j]; + j -= 1; + }else{ + ans[k] = nums[i] * nums[i]; + i += 1; + } + k -= 1; + } + ans + } +} +``` ----------------------- * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw) From 597f24d2a07341d2dadcc1ecbfdbff372863377c Mon Sep 17 00:00:00 2001 From: boom-jumper <56831966+boom-jumper@users.noreply.github.com> Date: Thu, 27 May 2021 20:30:37 +0800 Subject: [PATCH 02/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A00232=E7=94=A8=E6=A0=88?= =?UTF-8?q?=E5=AE=9E=E7=8E=B0=E9=98=9F=E5=88=97=20python3=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/0232.用栈实现队列.md | 44 +++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/problems/0232.用栈实现队列.md b/problems/0232.用栈实现队列.md index 10314a08..c2af71f7 100644 --- a/problems/0232.用栈实现队列.md +++ b/problems/0232.用栈实现队列.md @@ -282,6 +282,50 @@ class MyQueue { Python： +```python +# 使用两个栈实现先进先出的队列 +class MyQueue: + def __init__(self): + """ + Initialize your data structure here. + """ + self.stack1 = list() + self.stack2 = list() + + def push(self, x: int) -> None: + """ + Push element x to the back of queue. + """ + # self.stack1用于接受元素 + self.stack1.append(x) + + def pop(self) -> int: + """ + Removes the element from in front of queue and returns that element. + """ + # self.stack2用于弹出元素，如果self.stack2为[],则将self.stack1中元素全部弹出给self.stack2 + if self.stack2 == []: + while self.stack1: + tmp = self.stack1.pop() + self.stack2.append(tmp) + return self.stack2.pop() + + def peek(self) -> int: + """ + Get the front element. + """ + if self.stack2 == []: + while self.stack1: + tmp = self.stack1.pop() + self.stack2.append(tmp) + return self.stack2[-1] + + def empty(self) -> bool: + """ + Returns whether the queue is empty. + """ + return self.stack1 == [] and self.stack2 == [] +``` Go： From 0ae9d1808cf4db850f28ad9cfa837506bfec9588 Mon Sep 17 00:00:00 2001 From: boom-jumper <56831966+boom-jumper@users.noreply.github.com> Date: Thu, 27 May 2021 20:37:53 +0800 Subject: [PATCH 03/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A00150=E9=80=86=E6=B3=A2?= =?UTF-8?q?=E5=85=B0=E8=A1=A8=E8=BE=BE=E5=BC=8F=E6=B1=82=E5=80=BC=20python?= =?UTF-8?q?3=20=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0150.逆波兰表达式求值.md | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/problems/0150.逆波兰表达式求值.md b/problems/0150.逆波兰表达式求值.md index e38bc1a3..c8b0da08 100644 --- a/problems/0150.逆波兰表达式求值.md +++ b/problems/0150.逆波兰表达式求值.md @@ -224,6 +224,22 @@ var evalRPN = function(tokens) { }; ``` +python3 + +```python +def evalRPN(tokens) -> int: + stack = list() + for i in range(len(tokens)): + if tokens[i] not in ["+", "-", "*", "/"]: + stack.append(tokens[i]) + else: + tmp1 = stack.pop() + tmp2 = stack.pop() + res = eval(tmp2+tokens[i]+tmp1) + stack.append(str(int(res))) + return stack[-1] +``` + ----------------------- * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw) From d7235d9f51b532dda387bf6e00be225f931ed275 Mon Sep 17 00:00:00 2001 From: NevS <1173325467@qq.com> Date: Thu, 27 May 2021 21:39:32 +0800 Subject: [PATCH 04/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=2002.07.=E9=93=BE?= =?UTF-8?q?=E8=A1=A8=E7=9B=B8=E4=BA=A4=20go=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/面试题02.07.链表相交.md | 36 +++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/problems/面试题02.07.链表相交.md b/problems/面试题02.07.链表相交.md index 9e97264c..13014dd1 100644 --- a/problems/面试题02.07.链表相交.md +++ b/problems/面试题02.07.链表相交.md @@ -155,6 +155,42 @@ Python： Go： +```go +func getIntersectionNode(headA, headB *ListNode) *ListNode { + curA := headA + curB := headB + lenA, lenB := 0, 0 + // 求A，B的长度 + for curA != nil { + curA = curA.Next + lenA++ + } + for curB != nil { + curB = curB.Next + lenB++ + } + var step int + var fast, slow *ListNode + // 请求长度差，并且让更长的链表先走相差的长度 + if lenA > lenB { + step = lenA - lenB + fast, slow = headA, headB + } else { + step = lenB - lenA + fast, slow = headB, headA + } + for i:=0; i < step; i++ { + fast = fast.Next + } + // 遍历两个链表遇到相同则跳出遍历 + for fast != slow { + fast = fast.Next + slow = slow.Next + } + return fast +} +``` + javaScript: ```js From 7f3b661add171dab5cee5ebae5516962cf55cf3e Mon Sep 17 00:00:00 2001 From: zqh1059405318 <1059405318@qq.com> Date: Thu, 27 May 2021 23:44:00 +0800 Subject: [PATCH 05/27] =?UTF-8?q?=E6=9B=B4=E6=96=B00541.=E5=8F=8D=E8=BD=AC?= =?UTF-8?q?=E5=AD=97=E7=AC=A6=E4=B8=B2II=20Java=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0541.反转字符串II.md | 33 ++++++++++++++---------------- 1 file changed, 15 insertions(+), 18 deletions(-) diff --git a/problems/0541.反转字符串II.md b/problems/0541.反转字符串II.md index db53caf7..6c8f3e94 100644 --- a/problems/0541.反转字符串II.md +++ b/problems/0541.反转字符串II.md @@ -106,27 +106,24 @@ Java： class Solution { public String reverseStr(String s, int k) { StringBuffer res = new StringBuffer(); - - for (int i = 0; i < s.length(); i += (2 * k)) { + int length = s.length(); + int start = 0; + while (start < length) { + // 找到k处和2k处 StringBuffer temp = new StringBuffer(); - // 剩余字符大于 k 个，每隔 2k 个字符的前 k 个字符进行反转 - if (i + k <= s.length()) { - // 反转前 k 个字符 - temp.append(s.substring(i, i + k)); - res.append(temp.reverse()); + // 与length进行判断，如果大于length了，那就将其置为length + int firstK = (start + k > length) ? length : start + k; + int secondK = (start + (2 * k) > length) ? length : start + (2 * k); - // 反转完前 k 个字符之后，如果紧接着还有 k 个字符，则直接加入这 k 个字符 - if (i + 2 * k <= s.length()) { - res.append(s.substring(i + k, i + 2 * k)); - // 不足 k 个字符，则直接加入剩下所有字符 - } else { - res.append(s.substring(i + k, s.length())); - } - continue; - } - // 剩余字符少于 k 个，则将剩余字符全部反转。 - temp.append(s.substring(i, s.length())); + //无论start所处位置，至少会反转一次 + temp.append(s.substring(start, firstK)); res.append(temp.reverse()); + + // 如果firstK到secondK之间有元素，这些元素直接放入res里即可。 + if (firstK < secondK) { //此时剩余长度一定大于k。 + res.append(s.substring(firstK, secondK)); + } + start += (2 * k); } return res.toString(); } From ce1a80b0166b8f37c03c3ed867dc6d89279f345a Mon Sep 17 00:00:00 2001 From: jojoo15 <75017412+jojoo15@users.noreply.github.com> Date: Thu, 27 May 2021 18:01:48 +0200 Subject: [PATCH 06/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200078.=E5=AD=90?= =?UTF-8?q?=E9=9B=86=20python3=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 添加 0078.子集 python3版本 --- problems/0078.子集.md | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/problems/0078.子集.md b/problems/0078.子集.md index 17c4fb5c..0b2f3c09 100644 --- a/problems/0078.子集.md +++ b/problems/0078.子集.md @@ -205,7 +205,20 @@ class Solution { ``` Python： - +```python3 +class Solution: + def subsets(self, nums: List[int]) -> List[List[int]]: + res = [] + path = [] + def backtrack(nums,startIndex): + res.append(path[:]) #收集子集，要放在终止添加的上面，否则会漏掉自己 + for i in range(startIndex,len(nums)): #当startIndex已经大于数组的长度了，就终止了，for循环本来也结束了，所以不需要终止条件 + path.append(nums[i]) + backtrack(nums,i+1) #递归 + path.pop() #回溯 + backtrack(nums,0) + return res +``` Go： ```Go From c722642392ab8853f91ffac654149531b8117973 Mon Sep 17 00:00:00 2001 From: NevS <1173325467@qq.com> Date: Fri, 28 May 2021 00:33:17 +0800 Subject: [PATCH 07/27] =?UTF-8?q?=E6=9B=B4=E6=96=B0=200142.=E7=8E=AF?= =?UTF-8?q?=E5=BD=A2=E9=93=BE=E8=A1=A8II=20go=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 1、原先的Go版本代码显示错乱，一部分代码未显示 2、去掉多余判断，让代码更简洁 --- problems/0142.环形链表II.md | 28 +++++++++++----------------- 1 file changed, 11 insertions(+), 17 deletions(-) diff --git a/problems/0142.环形链表II.md b/problems/0142.环形链表II.md index 15c2d1f9..9deb1e0c 100644 --- a/problems/0142.环形链表II.md +++ b/problems/0142.环形链表II.md @@ -234,25 +234,19 @@ class Solution: ``` Go： -```func detectCycle(head *ListNode) *ListNode { - if head ==nil{ - return head - } - slow:=head - fast:=head.Next - - for fast!=nil&&fast.Next!=nil{ - if fast==slow{ - slow=head - fast=fast.Next - for fast!=slow { - fast=fast.Next - slow=slow.Next +```go +func detectCycle(head *ListNode) *ListNode { + slow, fast := head, head + for fast != nil && fast.Next != nil { + slow = slow.Next + fast = fast.Next.Next + if slow == fast { + for slow != head { + slow = slow.Next + head = head.Next } - return slow + return head } - fast=fast.Next.Next - slow=slow.Next } return nil } From b41866f1f4a2fcc7c631bbaf9de5166465a7586c Mon Sep 17 00:00:00 2001 From: jojoo15 <75017412+jojoo15@users.noreply.github.com> Date: Thu, 27 May 2021 18:57:04 +0200 Subject: [PATCH 08/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200090.=E5=AD=90?= =?UTF-8?q?=E9=9B=86=20python3=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 添加 0090.子集 python3版本 --- problems/0090.子集II.md | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/problems/0090.子集II.md b/problems/0090.子集II.md index 6b12a95b..71aef5c7 100644 --- a/problems/0090.子集II.md +++ b/problems/0090.子集II.md @@ -208,7 +208,23 @@ class Solution { ``` Python： - +```python3 +class Solution: + def subsetsWithDup(self, nums: List[int]) -> List[List[int]]: + res = [] #存放符合条件结果的集合 + path = [] #用来存放符合条件结果 + def backtrack(nums,startIndex): + res.append(path[:]) + for i in range(startIndex,len(nums)): + if i > startIndex and nums[i] == nums[i - 1]: #我们要对同一树层使用过的元素进行跳过 + continue + path.append(nums[i]) + backtrack(nums,i+1) #递归 + path.pop() #回溯 + nums = sorted(nums) #去重需要排序 + backtrack(nums,0) + return res +``` Go： ```Go From 60624686a894dadcfefb79cd38e40f0308217f93 Mon Sep 17 00:00:00 2001 From: jojoo15 <75017412+jojoo15@users.noreply.github.com> Date: Fri, 28 May 2021 00:09:28 +0200 Subject: [PATCH 09/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200491.=E9=80=92?= =?UTF-8?q?=E5=A2=9E=E5=AD=90=E5=BA=8F=E5=88=97=20python3=E7=89=88?= =?UTF-8?q?=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 添加 0491.递增子序列 python3版本 --- problems/0491.递增子序列.md | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/problems/0491.递增子序列.md b/problems/0491.递增子序列.md index 691f7aef..5538a2c9 100644 --- a/problems/0491.递增子序列.md +++ b/problems/0491.递增子序列.md @@ -229,7 +229,28 @@ class Solution { Python： - +```python3 +class Solution: + def findSubsequences(self, nums: List[int]) -> List[List[int]]: + res = [] + path = [] + def backtrack(nums,startIndex): + repeat = [] #这里使用数组来进行去重操作 + if len(path) >=2: + res.append(path[:]) #注意这里不要加return，要取树上的节点 + for i in range(startIndex,len(nums)): + if nums[i] in repeat: + continue + if len(path) >= 1: + if nums[i] < path[-1]: + continue + repeat.append(nums[i]) #记录这个元素在本层用过了，本层后面不能再用了 + path.append(nums[i]) + backtrack(nums,i+1) + path.pop() + backtrack(nums,0) + return res +``` Go： From 6c33729d9f15ea6db9f9497c70bb87081394b2c1 Mon Sep 17 00:00:00 2001 From: fusunx <1102654482@qq.com> Date: Fri, 28 May 2021 08:11:56 +0800 Subject: [PATCH 10/27] =?UTF-8?q?0055.=E8=B7=B3=E8=B7=83=E6=B8=B8=E6=88=8F?= =?UTF-8?q?.md=20Javascript?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0055.跳跃游戏.md | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/problems/0055.跳跃游戏.md b/problems/0055.跳跃游戏.md index b4b42a4a..8618515e 100644 --- a/problems/0055.跳跃游戏.md +++ b/problems/0055.跳跃游戏.md @@ -141,7 +141,20 @@ func canJUmp(nums []int) bool { } ``` - +Javascript: +```Javascript +var canJump = function(nums) { + if(nums.length === 1) return true + let cover = 0 + for(let i = 0; i <= cover; i++) { + cover = Math.max(cover, i + nums[i]) + if(cover >= nums.length - 1) { + return true + } + } + return false +}; +``` ----------------------- From c01a968b92f97c98433432bfabc769c22d5f0f1c Mon Sep 17 00:00:00 2001 From: xll <18574553598@163.com> Date: Fri, 28 May 2021 11:05:37 +0800 Subject: [PATCH 11/27] =?UTF-8?q?0404=E5=B7=A6=E5=8F=B6=E5=AD=90=E4=B9=8B?= =?UTF-8?q?=E5=92=8CJavaScript=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0404.左叶子之和.md | 46 +++++++++++++++++++++++++++++++- 1 file changed, 45 insertions(+), 1 deletion(-) diff --git a/problems/0404.左叶子之和.md b/problems/0404.左叶子之和.md index 30d702b4..e5daa9db 100644 --- a/problems/0404.左叶子之和.md +++ b/problems/0404.左叶子之和.md @@ -226,7 +226,51 @@ class Solution: ``` Go： - +JavaScript: +递归版本 +```javascript +var sumOfLeftLeaves = function(root) { + //采用后序遍历 递归遍历 + // 1. 确定递归函数参数 + const nodesSum = function(node){ + // 2. 确定终止条件 + if(node===null){ + return 0; + } + let leftValue = sumOfLeftLeaves(node.left); + let rightValue = sumOfLeftLeaves(node.right); + // 3. 单层递归逻辑 + let midValue = 0; + if(node.left&&node.left.left===null&&node.left.right===null){ + midValue = node.left.val; + } + let sum = midValue + leftValue + rightValue; + return sum; + } + return nodesSum(root); +}; +``` +迭代版本 +```javascript +var sumOfLeftLeaves = function(root) { + //采用层序遍历 + if(root===null){ + return null; + } + let queue = []; + let sum = 0; + queue.push(root); + while(queue.length){ + let node = queue.shift(); + if(node.left!==null&&node.left.left===null&&node.left.right===null){ + sum+=node.left.val; + } + node.left&&queue.push(node.left); + node.right&&queue.push(node.right); + } + return sum; +}; +``` From f6a9d649ea71d8d0685423278b8c3879fb8143f4 Mon Sep 17 00:00:00 2001 From: LiangDazhu <42199191+LiangDazhu@users.noreply.github.com> Date: Fri, 28 May 2021 16:30:11 +0800 Subject: [PATCH 12/27] =?UTF-8?q?Update=200343.=E6=95=B4=E6=95=B0=E6=8B=86?= =?UTF-8?q?=E5=88=86.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Added python version code 有一行文本我觉得写重复了, 给删掉了 --- problems/0343.整数拆分.md | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/problems/0343.整数拆分.md b/problems/0343.整数拆分.md index c9423a1a..fefaa293 100644 --- a/problems/0343.整数拆分.md +++ b/problems/0343.整数拆分.md @@ -51,10 +51,6 @@ dp[i]的定义讲贯彻整个解题过程，下面哪一步想不懂了，就想 **那有同学问了，j怎么就不拆分呢？** -j是从1开始遍历，拆分j的情况，在遍历j的过程中其实都计算过了。 - -**那有同学问了，j怎么就不拆分呢？** - j是从1开始遍历，拆分j的情况，在遍历j的过程中其实都计算过了。那么从1遍历j，比较(i - j) * j和dp[i - j] * j 取最大的。递推公式：dp[i] = max(dp[i], max((i - j) * j, dp[i - j] * j)); 也可以这么理解，j * (i - j) 是单纯的把整数拆分为两个数相乘，而j * dp[i - j]是拆分成两个以及两个以上的个数相乘。 @@ -213,8 +209,19 @@ class Solution { ``` Python： - - +```python +class Solution: + def integerBreak(self, n: int) -> int: + dp = [0] * (n + 1) + dp[2] = 1 + for i in range(3, n + 1): + # 假设对正整数 i 拆分出的第一个正整数是 j（1 <= j < i），则有以下两种方案： + # 1) 将 i 拆分成 j 和 i−j 的和，且 i−j 不再拆分成多个正整数，此时的乘积是 j * (i-j) + # 2) 将 i 拆分成 j 和 i−j 的和，且 i−j 继续拆分成多个正整数，此时的乘积是 j * dp[i-j] + for j in range(1, i): + dp[i] = max(dp[i], max(j * (i - j), j * dp[i - j])) + return dp[n] +``` Go： From f9686c7d84422f9403ded97760c8b2e2d653e090 Mon Sep 17 00:00:00 2001 From: jojoo15 <75017412+jojoo15@users.noreply.github.com> Date: Fri, 28 May 2021 11:19:43 +0200 Subject: [PATCH 13/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200046.=E5=85=A8?= =?UTF-8?q?=E6=8E=92=E5=88=97=20python3=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 添加 0046.全排列 python3版本 --- problems/0046.全排列.md | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/problems/0046.全排列.md b/problems/0046.全排列.md index 0beb45cf..6e5b528e 100644 --- a/problems/0046.全排列.md +++ b/problems/0046.全排列.md @@ -182,7 +182,26 @@ class Solution { ``` Python： - +```python3 +class Solution: + def permute(self, nums: List[int]) -> List[List[int]]: + res = [] #存放符合条件结果的集合 + path = [] #用来存放符合条件的结果 + used = [] #用来存放已经用过的数字 + def backtrack(nums,used): + if len(path) == len(nums): + return res.append(path[:]) #此时说明找到了一组 + for i in range(0,len(nums)): + if nums[i] in used: + continue #used里已经收录的元素，直接跳过 + path.append(nums[i]) + used.append(nums[i]) + backtrack(nums,used) + used.pop() + path.pop() + backtrack(nums,used) + return res +``` Go： ```Go From 14221a52fe02d489330b6fc254d187de99c99ae2 Mon Sep 17 00:00:00 2001 From: jojoo15 <75017412+jojoo15@users.noreply.github.com> Date: Fri, 28 May 2021 11:26:43 +0200 Subject: [PATCH 14/27] =?UTF-8?q?=E6=9B=B4=E6=96=B0=200046.=E5=85=A8?= =?UTF-8?q?=E6=8E=92=E5=88=97=20python3=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 更新 0046.全排列 python3版本，比之前那个更简洁一点，少了个used数组 --- problems/0046.全排列.md | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/problems/0046.全排列.md b/problems/0046.全排列.md index 0beb45cf..3ead73e3 100644 --- a/problems/0046.全排列.md +++ b/problems/0046.全排列.md @@ -182,7 +182,23 @@ class Solution { ``` Python： - +```python3 +class Solution: + def permute(self, nums: List[int]) -> List[List[int]]: + res = [] #存放符合条件结果的集合 + path = [] #用来存放符合条件的结果 + def backtrack(nums): + if len(path) == len(nums): + return res.append(path[:]) #此时说明找到了一组 + for i in range(0,len(nums)): + if nums[i] in path: #path里已经收录的元素，直接跳过 + continue + path.append(nums[i]) + backtrack(nums) #递归 + path.pop() #回溯 + backtrack(nums) + return res +``` Go： ```Go From 60d89d920053650736e17fa814d020deedcda89e Mon Sep 17 00:00:00 2001 From: NevS <1173325467@qq.com> Date: Fri, 28 May 2021 22:59:27 +0800 Subject: [PATCH 15/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200349.=E4=B8=A4?= =?UTF-8?q?=E4=B8=AA=E6=95=B0=E7=BB=84=E7=9A=84=E4=BA=A4=E9=9B=86=20go?= =?UTF-8?q?=E7=89=88?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0349.两个数组的交集.md | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/problems/0349.两个数组的交集.md b/problems/0349.两个数组的交集.md index fe019a0a..090480a4 100644 --- a/problems/0349.两个数组的交集.md +++ b/problems/0349.两个数组的交集.md @@ -132,6 +132,23 @@ class Solution: Go： +```go +func intersection(nums1 []int, nums2 []int) []int { + m := make(map[int]int) + for _, v := range nums1 { + m[v] = 1 + } + var res []int + // 利用count>0，实现重复值只拿一次放入返回结果中 + for _, v := range nums2 { + if count, ok := m[v]; ok && count > 0 { + res = append(res, v) + m[v]-- + } + } + return res +} +``` javaScript: From 1590897824de40843710804d6a0397eca0131ee1 Mon Sep 17 00:00:00 2001 From: LiangDazhu <42199191+LiangDazhu@users.noreply.github.com> Date: Fri, 28 May 2021 23:33:19 +0800 Subject: [PATCH 16/27] =?UTF-8?q?Update=200096.=E4=B8=8D=E5=90=8C=E7=9A=84?= =?UTF-8?q?=E4=BA=8C=E5=8F=89=E6=90=9C=E7=B4=A2=E6=A0=91.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Added python version code --- problems/0096.不同的二叉搜索树.md | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/problems/0096.不同的二叉搜索树.md b/problems/0096.不同的二叉搜索树.md index cee0102f..a9631315 100644 --- a/problems/0096.不同的二叉搜索树.md +++ b/problems/0096.不同的二叉搜索树.md @@ -186,7 +186,16 @@ class Solution { ``` Python： - +```python +class Solution: + def numTrees(self, n: int) -> int: + dp = [0] * (n + 1) + dp[0], dp[1] = 1, 1 + for i in range(2, n + 1): + for j in range(1, i + 1): + dp[i] += dp[j - 1] * dp[i - j] + return dp[-1] +``` Go： ```Go From c4de753d6db1548205de14efdb4fc9194d7223c4 Mon Sep 17 00:00:00 2001 From: phoenix Date: Sat, 29 May 2021 08:07:50 +0800 Subject: [PATCH 17/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200020.=E6=9C=89?= =?UTF-8?q?=E6=95=88=E7=9A=84=E6=8B=AC=E5=8F=B7=20Ruby=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/0015.三数之和.md | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/problems/0015.三数之和.md b/problems/0015.三数之和.md index 811fc316..4f4ec63a 100644 --- a/problems/0015.三数之和.md +++ b/problems/0015.三数之和.md @@ -336,6 +336,23 @@ var threeSum = function(nums) { ``` +ruby: +```ruby +def is_valid(strs) + symbol_map = {')' => '(', '}' => '{', ']' => '['} + stack = [] + strs.size.times {|i| + c = strs[i] + if symbol_map.has_key?(c) + top_e = stack.shift + return false if symbol_map[c] != top_e + else + stack.unshift(c) + end + } + stack.empty? +end +``` ----------------------- * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw) From bd95f6a248f9175216582225500e3c074f0c4180 Mon Sep 17 00:00:00 2001 From: phoenix Date: Sat, 29 May 2021 09:12:26 +0800 Subject: [PATCH 18/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200027.=E7=A7=BB?= =?UTF-8?q?=E9=99=A4=E5=85=83=E7=B4=A0=20Ruby=20=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0027.移除元素.md | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/problems/0027.移除元素.md b/problems/0027.移除元素.md index 8da0fb89..f0f61d06 100644 --- a/problems/0027.移除元素.md +++ b/problems/0027.移除元素.md @@ -186,6 +186,20 @@ var removeElement = (nums, val) => { }; ``` +Ruby: +```ruby +def remove_element(nums, val) + i = 0 + nums.each_index do |j| + if nums[j] != val + nums[i] = nums[j] + i+=1 + end + end + i +end +``` + ----------------------- * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw) * B站视频：[代码随想录](https://space.bilibili.com/525438321) From 5512ccdb63370be27a387acab0c1ae366607b089 Mon Sep 17 00:00:00 2001 From: xll <18574553598@163.com> Date: Sat, 29 May 2021 10:44:58 +0800 Subject: [PATCH 19/27] =?UTF-8?q?0513=E4=BA=8C=E5=8F=89=E6=A0=91=E5=B7=A6?= =?UTF-8?q?=E5=B0=8F=E8=A7=92=E7=9A=84=E5=80=BCJavaScript=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/0513.找树左下角的值.md | 47 ++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/problems/0513.找树左下角的值.md b/problems/0513.找树左下角的值.md index 5c9613e5..97464e3d 100644 --- a/problems/0513.找树左下角的值.md +++ b/problems/0513.找树左下角的值.md @@ -298,6 +298,53 @@ class Solution: ``` Go： +JavaScript: +1. 递归版本 +```javascript +var findBottomLeftValue = function(root) { + //首先考虑递归遍历 前序遍历 找到最大深度的叶子节点即可 + let maxPath = 0,resNode = null; + // 1. 确定递归函数的函数参数 + const dfsTree = function(node,curPath){ + // 2. 确定递归函数终止条件 + if(node.left===null&&node.right===null){ + if(curPath>maxPath){ + maxPath = curPath; + resNode = node.val; + } + // return ; + } + node.left&&dfsTree(node.left,curPath+1); + node.right&&dfsTree(node.right,curPath+1); + } + dfsTree(root,1); + return resNode; +}; +``` +2. 层序遍历 +```javascript +var findBottomLeftValue = function(root) { + //考虑层序遍历 记录最后一行的第一个节点 + let queue = []; + if(root===null){ + return null; + } + queue.push(root); + let resNode; + while(queue.length){ + let length = queue.length; + for(let i=0; i Date: Sat, 29 May 2021 16:13:32 +0800 Subject: [PATCH 20/27] =?UTF-8?q?=E7=BA=A0=E6=AD=A339.=E7=BB=84=E5=90=88?= =?UTF-8?q?=E6=80=BB=E5=92=8C=20Java=E7=89=88=E6=9C=AC=E4=BB=A3=E7=A0=81?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0039.组合总和.md | 40 +++++++++++++++-------------------- 1 file changed, 17 insertions(+), 23 deletions(-) diff --git a/problems/0039.组合总和.md b/problems/0039.组合总和.md index ab118ee0..a83e42f4 100644 --- a/problems/0039.组合总和.md +++ b/problems/0039.组合总和.md @@ -237,34 +237,28 @@ public: Java： ```Java +// 剪枝优化 class Solution { - List> lists = new ArrayList<>(); - Deque deque = new LinkedList<>(); - - public List> combinationSum3(int k, int n) { - int[] arr = new int[]{1, 2, 3, 4, 5, 6, 7, 8, 9}; - backTracking(arr, n, k, 0); - return lists; + public List> combinationSum(int[] candidates, int target) { + List> res = new ArrayList<>(); + Arrays.sort(candidates); // 先进行排序 + backtracking(res, new ArrayList<>(), candidates, target, 0, 0); + return res; } - public void backTracking(int[] arr, int n, int k, int startIndex) { - //如果 n 小于0，没必要继续本次递归，已经不符合要求了 - if (n < 0) { + public void backtracking(List> res, List path, int[] candidates, int target, int sum, int idx) { + // 找到了数字和为 target 的组合 + if (sum == target) { + res.add(new ArrayList<>(path)); return; } - if (deque.size() == k) { - if (n == 0) { - lists.add(new ArrayList(deque)); - } - return; - } - for (int i = startIndex; i < arr.length - (k - deque.size()) + 1; i++) { - deque.push(arr[i]); - //减去当前元素 - n -= arr[i]; - backTracking(arr, n, k, i + 1); - //恢复n - n += deque.pop(); + + for (int i = idx; i < candidates.length; i++) { + // 如果 sum + candidates[i] > target 就终止遍历 + if (sum + candidates[i] > target) break; + path.add(candidates[i]); + backtracking(res, path, candidates, target, sum + candidates[i], i); + path.remove(path.size() - 1); // 回溯，移除路径 path 最后一个元素 } } } From b1b389da3204c4faf0c65519e8f58cf59afe18d4 Mon Sep 17 00:00:00 2001 From: xll <18574553598@163.com> Date: Sat, 29 May 2021 22:20:52 +0800 Subject: [PATCH 21/27] =?UTF-8?q?=E4=BA=8C=E5=8F=89=E6=A0=91=E8=B7=AF?= =?UTF-8?q?=E5=BE=84=E6=80=BB=E5=92=8CJavaScript=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0112.路径总和.md | 56 +++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) diff --git a/problems/0112.路径总和.md b/problems/0112.路径总和.md index b4a3f38b..4ccd8912 100644 --- a/problems/0112.路径总和.md +++ b/problems/0112.路径总和.md @@ -524,6 +524,62 @@ let pathSum = function (root, targetSum) { }; ``` +0112 路径总和 +```javascript +var hasPathSum = function(root, targetSum) { + //递归方法 + // 1. 确定函数参数 + const traversal = function(node,count){ + // 2. 确定终止条件 + if(node.left===null&&node.right===null&&count===0){ + return true; + } + if(node.left===null&&node.right===null){ + return false; + } + //3. 单层递归逻辑 + if(node.left){ + if(traversal(node.left,count-node.left.val)){ + return true; + } + } + if(node.right){ + if(traversal(node.right,count-node.right.val)){ + return true; + } + } + return false; + } + if(root===null){ + return false; + } + return traversal(root,targetSum-root.val); +}; +``` +113 路径总和 +```javascript +var pathSum = function(root, targetSum) { + //递归方法 + let resPath = [],curPath = []; + // 1. 确定递归函数参数 + const travelTree = function(node,count){ + curPath.push(node.val); + count-=node.val; + if(node.left===null&&node.right===null&&count===0){ + resPath.push([...curPath]); + } + node.left&&travelTree(node.left,count); + node.right&&travelTree(node.right,count); + let cur = curPath.pop(); + count-=cur; + } + if(root===null){ + return resPath; + } + travelTree(root,targetSum); + return resPath; +}; +``` From 406d44819ac878232b49a6ffafad06d944643a6a Mon Sep 17 00:00:00 2001 From: X-shuffle <53906918+X-shuffle@users.noreply.github.com> Date: Sun, 30 May 2021 10:38:30 +0800 Subject: [PATCH 22/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=20=E4=BA=8C=E5=8F=89?= =?UTF-8?q?=E6=A0=91=E7=9A=84=E5=B1=82=E5=BA=8F=E9=81=8D=E5=8E=86=20GO?= =?UTF-8?q?=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 添加 二叉树的层序遍历 GO版本 --- problems/0102.二叉树的层序遍历.md | 243 ++++++++++++++++++++++ 1 file changed, 243 insertions(+) diff --git a/problems/0102.二叉树的层序遍历.md b/problems/0102.二叉树的层序遍历.md index ee93911e..00607082 100644 --- a/problems/0102.二叉树的层序遍历.md +++ b/problems/0102.二叉树的层序遍历.md @@ -836,6 +836,249 @@ func levelOrder(root *TreeNode) [][]int { return result } ``` +> 二叉树的层序遍历（GO语言完全版） + +```go +/** +102. 二叉树的层序遍历 + */ +func levelOrder(root *TreeNode) [][]int { + res:=[][]int{} + if root==nil{//防止为空 + return res + } + queue:=list.New() + queue.PushBack(root) + var tmpArr []int + for queue.Len()>0 { + length:=queue.Len()//保存当前层的长度，然后处理当前层（十分重要，防止添加下层元素影响判断层中元素的个数） + for i:=0;i0{ + length:=queue.Len() + tmp:=[]int{} + for i:=0;i0{ + length:=queue.Len() + tmp:=[]int{} + for i:=0;i0 { + length:=queue.Len()//保存当前层的长度，然后处理当前层（十分重要，防止添加下层元素影响判断层中元素的个数） + for i:=0;i0{ + length:=queue.Len()//记录当前层的数量 + var tmp []int + for T:=0;T0 { + length:=queue.Len()//保存当前层的长度，然后处理当前层（十分重要，防止添加下层元素影响判断层中元素的个数） + for i:=0;i max { + max = val + } + } + return max +} +/** +116. 填充每个节点的下一个右侧节点指针 +117. 填充每个节点的下一个右侧节点指针 II + */ + +func connect(root *Node) *Node { + res:=[][]*Node{} + if root==nil{//防止为空 + return root + } + queue:=list.New() + queue.PushBack(root) + var tmpArr []*Node + for queue.Len()>0 { + length:=queue.Len()//保存当前层的长度，然后处理当前层（十分重要，防止添加下层元素影响判断层中元素的个数） + for i:=0;i Date: Sun, 30 May 2021 14:07:55 +0800 Subject: [PATCH 23/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200203.=E7=A7=BB?= =?UTF-8?q?=E9=99=A4=E9=93=BE=E8=A1=A8=E5=85=83=E7=B4=A0=20python3?= =?UTF-8?q?=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0203.移除链表元素.md | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/problems/0203.移除链表元素.md b/problems/0203.移除链表元素.md index dce5d265..cac9f233 100644 --- a/problems/0203.移除链表元素.md +++ b/problems/0203.移除链表元素.md @@ -208,7 +208,23 @@ public ListNode removeElements(ListNode head, int val) { ``` Python： - +```python +# Definition for singly-linked list. +# class ListNode: +# def __init__(self, val=0, next=None): +# self.val = val +# self.next = next +class Solution: + def removeElements(self, head: ListNode, val: int) -> ListNode: + dummy_head = ListNode(next=head) #添加一个虚拟节点 + cur = dummy_head + while(cur.next!=None): + if(cur.next.val == val): + cur.next = cur.next.next #删除cur.next节点 + else: + cur = cur.next + return dummy_head.next +``` Go： From 5e1860876b8d594d2e4d74a03772495c06cc357f Mon Sep 17 00:00:00 2001 From: evanlai Date: Sun, 30 May 2021 14:10:11 +0800 Subject: [PATCH 24/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200206.=E7=BF=BB?= =?UTF-8?q?=E8=BD=AC=E9=93=BE=E8=A1=A8=20python3=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0206.翻转链表.md | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/problems/0206.翻转链表.md b/problems/0206.翻转链表.md index 52ef6484..7c002382 100644 --- a/problems/0206.翻转链表.md +++ b/problems/0206.翻转链表.md @@ -143,7 +143,25 @@ class Solution { ``` Python： - +```python +#双指针 +# Definition for singly-linked list. +# class ListNode: +# def __init__(self, val=0, next=None): +# self.val = val +# self.next = next +class Solution: + def reverseList(self, head: ListNode) -> ListNode: + cur = head + pre = None + while(cur!=None): + temp = cur.next # 保存一下 cur的下一个节点，因为接下来要改变cur->next + cur.next = pre #反转 + #更新pre、cur指针 + pre = cur + cur = temp + return pre +``` Go： From 013ba0575ed1729e8a1c31c251313e379d38adc2 Mon Sep 17 00:00:00 2001 From: evanlai Date: Sun, 30 May 2021 14:13:38 +0800 Subject: [PATCH 25/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200019.=E5=88=A0?= =?UTF-8?q?=E9=99=A4=E9=93=BE=E8=A1=A8=E7=9A=84=E5=80=92=E6=95=B0=E7=AC=AC?= =?UTF-8?q?N=E4=B8=AA=E8=8A=82=E7=82=B9=20python3=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...0019.删除链表的倒数第N个节点.md | 24 +++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/problems/0019.删除链表的倒数第N个节点.md b/problems/0019.删除链表的倒数第N个节点.md index 7d2fe97e..52735794 100644 --- a/problems/0019.删除链表的倒数第N个节点.md +++ b/problems/0019.删除链表的倒数第N个节点.md @@ -112,6 +112,30 @@ class Solution { } } ``` + +Python: +```python +# Definition for singly-linked list. +# class ListNode: +# def __init__(self, val=0, next=None): +# self.val = val +# self.next = next +class Solution: + def removeNthFromEnd(self, head: ListNode, n: int) -> ListNode: + head_dummy = ListNode() + head_dummy.next = head + + slow, fast = head_dummy, head_dummy + while(n!=0): #fast先往前走n步 + fast = fast.next + n -= 1 + while(fast.next!=None): + slow = slow.next + fast = fast.next + #fast 走到结尾后，slow的下一个节点为倒数第N个节点 + slow.next = slow.next.next #删除 + return head_dummy.next +``` Go: ```Go /** From e98fb5a56f256371d01ed7e9456aa0fde805626f Mon Sep 17 00:00:00 2001 From: evanlai Date: Sun, 30 May 2021 14:21:41 +0800 Subject: [PATCH 26/27] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=20=E9=9D=A2=E8=AF=95?= =?UTF-8?q?=E9=A2=9802.07.=E9=93=BE=E8=A1=A8=E7=9B=B8=E4=BA=A4=20python3?= =?UTF-8?q?=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/面试题02.07.链表相交.md | 37 +++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/problems/面试题02.07.链表相交.md b/problems/面试题02.07.链表相交.md index 13014dd1..78f34e71 100644 --- a/problems/面试题02.07.链表相交.md +++ b/problems/面试题02.07.链表相交.md @@ -151,7 +151,44 @@ public class Solution { ``` Python： +```python +# Definition for singly-linked list. +# class ListNode: +# def __init__(self, x): +# self.val = x +# self.next = None +class Solution: + def getIntersectionNode(self, headA: ListNode, headB: ListNode) -> ListNode: + lengthA,lengthB = 0,0 + curA,curB = headA,headB + while(curA!=None): #求链表A的长度 + curA = curA.next + lengthA +=1 + + while(curB!=None): #求链表B的长度 + curB = curB.next + lengthB +=1 + + curA, curB = headA, headB + + if lengthB>lengthA: #让curA为最长链表的头，lenA为其长度 + lengthA, lengthB = lengthB, lengthA + curA, curB = curB, curA + + gap = lengthA - lengthB #求长度差 + while(gap!=0): + curA = curA.next #让curA和curB在同一起点上 + gap -= 1 + + while(curA!=None): + if curA == curB: + return curA + else: + curA = curA.next + curB = curB.next + return None +``` Go： From bf2ffec6674a429663a11aca03abbd9f36a9864c Mon Sep 17 00:00:00 2001 From: LiangDazhu <42199191+LiangDazhu@users.noreply.github.com> Date: Sun, 30 May 2021 19:21:51 +0800 Subject: [PATCH 27/27] =?UTF-8?q?Update=200416.=E5=88=86=E5=89=B2=E7=AD=89?= =?UTF-8?q?=E5=92=8C=E5=AD=90=E9=9B=86.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Added python version code --- problems/0416.分割等和子集.md | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/problems/0416.分割等和子集.md b/problems/0416.分割等和子集.md index e69eb1a4..55d200e2 100644 --- a/problems/0416.分割等和子集.md +++ b/problems/0416.分割等和子集.md @@ -222,8 +222,18 @@ class Solution { ``` Python： - - +```python +class Solution: + def canPartition(self, nums: List[int]) -> bool: + taraget = sum(nums) + if taraget % 2 == 1: return False + taraget //= 2 + dp = [0] * 10001 + for i in range(len(nums)): + for j in range(taraget, nums[i] - 1, -1): + dp[j] = max(dp[j], dp[j - nums[i]] + nums[i]) + return taraget == dp[taraget] +``` Go：