From 59c86a7023989e3cb3195615f30a0a99e39fa556 Mon Sep 17 00:00:00 2001 From: fw_qaq Date: Wed, 29 Mar 2023 18:15:26 +0800 Subject: [PATCH 01/29] =?UTF-8?q?Update=200844.=E6=AF=94=E8=BE=83=E5=90=AB?= =?UTF-8?q?=E9=80=80=E6=A0=BC=E7=9A=84=E5=AD=97=E7=AC=A6=E4=B8=B2.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0844.比较含退格的字符串.md | 29 ++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/problems/0844.比较含退格的字符串.md b/problems/0844.比较含退格的字符串.md index 6534f18c..40d5caa1 100644 --- a/problems/0844.比较含退格的字符串.md +++ b/problems/0844.比较含退格的字符串.md @@ -535,6 +535,35 @@ function getIndexAfterDel(s: string, startIndex: number): number { } ``` +### Rust + +> 双指针 + +```rust +impl Solution { + pub fn backspace_compare(s: String, t: String) -> bool { + let (s, t) = ( + s.chars().collect::>(), + t.chars().collect::>(), + ); + Self::get_string(s) == Self::get_string(t) + } + + pub fn get_string(mut chars: Vec) -> Vec { + let mut slow = 0; + for i in 0..chars.len() { + if chars[i] == '#' { + slow = (slow as u32).saturating_sub(1) as usize; + } else { + chars[slow] = chars[i]; + slow += 1; + } + } + chars.truncate(slow); + chars + } +} +``` From e4951bc9dba7ebaa5314d41a52b0a5d97b8a6cea Mon Sep 17 00:00:00 2001 From: fw_qaq Date: Wed, 29 Mar 2023 18:34:11 +0800 Subject: [PATCH 02/29] =?UTF-8?q?Update=200844.=E6=AF=94=E8=BE=83=E5=90=AB?= =?UTF-8?q?=E9=80=80=E6=A0=BC=E7=9A=84=E5=AD=97=E7=AC=A6=E4=B8=B2.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0844.比较含退格的字符串.md | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/problems/0844.比较含退格的字符串.md b/problems/0844.比较含退格的字符串.md index 40d5caa1..ac56f6f9 100644 --- a/problems/0844.比较含退格的字符串.md +++ b/problems/0844.比较含退格的字符串.md @@ -565,7 +565,27 @@ impl Solution { } ``` +> 双栈法 +```rust +impl Solution { + pub fn backspace_compare(s: String, t: String) -> bool { + Self::get_string(s) == Self::get_string(t) + } + + pub fn get_string(string: String) -> String { + let mut s = String::new(); + for c in string.chars() { + if c != '#' { + s.push(c); + } else if !s.is_empty() { + s.pop(); + } + } + s + } +} +```

From f7988e06dc26ffb93d93f41c8454b4d4504f5828 Mon Sep 17 00:00:00 2001 From: ayao98 <91120769+ayao98@users.noreply.github.com> Date: Fri, 31 Mar 2023 15:50:58 +0800 Subject: [PATCH 03/29] =?UTF-8?q?Update=200104.=E4=BA=8C=E5=8F=89=E6=A0=91?= =?UTF-8?q?=E7=9A=84=E6=9C=80=E5=A4=A7=E6=B7=B1=E5=BA=A6.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit c++语言部分，函数名和节点命名大小写有错误 --- problems/0104.二叉树的最大深度.md | 34 +++++++++++------------ 1 file changed, 17 insertions(+), 17 deletions(-) diff --git a/problems/0104.二叉树的最大深度.md b/problems/0104.二叉树的最大深度.md index b95e39c8..36578fd3 100644 --- a/problems/0104.二叉树的最大深度.md +++ b/problems/0104.二叉树的最大深度.md @@ -50,7 +50,7 @@ 代码如下： ```CPP -int getdepth(treenode* node) +int getdepth(TreeNode* node) ``` 2. 确定终止条件：如果为空节点的话，就返回0，表示高度为0。 @@ -76,14 +76,14 @@ return depth; ```CPP class solution { public: - int getdepth(treenode* node) { + int getdepth(TreeNode* node) { if (node == NULL) return 0; int leftdepth = getdepth(node->left); // 左 int rightdepth = getdepth(node->right); // 右 int depth = 1 + max(leftdepth, rightdepth); // 中 return depth; } - int maxdepth(treenode* root) { + int maxDepth(TreeNode* root) { return getdepth(root); } }; @@ -93,9 +93,9 @@ public: ```CPP class solution { public: - int maxdepth(treenode* root) { + int maxDepth(TreeNode* root) { if (root == null) return 0; - return 1 + max(maxdepth(root->left), maxdepth(root->right)); + return 1 + max(maxDepth(root->left), maxDepth(root->right)); } }; @@ -110,7 +110,7 @@ public: class solution { public: int result; - void getdepth(treenode* node, int depth) { + void getdepth(TreeNode* node, int depth) { result = depth > result ? depth : result; // 中 if (node->left == NULL && node->right == NULL) return ; @@ -127,7 +127,7 @@ public: } return ; } - int maxdepth(treenode* root) { + int maxDepth(TreeNode* root) { result = 0; if (root == NULL) return result; getdepth(root, 1); @@ -144,7 +144,7 @@ public: class solution { public: int result; - void getdepth(treenode* node, int depth) { + void getdepth(TreeNode* node, int depth) { result = depth > result ? depth : result; // 中 if (node->left == NULL && node->right == NULL) return ; if (node->left) { // 左 @@ -155,7 +155,7 @@ public: } return ; } - int maxdepth(treenode* root) { + int maxDepth(TreeNode* root) { result = 0; if (root == 0) return result; getdepth(root, 1); @@ -182,16 +182,16 @@ c++代码如下： ```CPP class solution { public: - int maxdepth(treenode* root) { + int maxDepth(TreeNode* root) { if (root == NULL) return 0; int depth = 0; - queue que; + queue que; que.push(root); while(!que.empty()) { int size = que.size(); depth++; // 记录深度 for (int i = 0; i < size; i++) { - treenode* node = que.front(); + TreeNode* node = que.front(); que.pop(); if (node->left) que.push(node->left); if (node->right) que.push(node->right); @@ -230,11 +230,11 @@ c++代码： ```CPP class solution { public: - int maxdepth(node* root) { + int maxDepth(Node* root) { if (root == 0) return 0; int depth = 0; for (int i = 0; i < root->children.size(); i++) { - depth = max (depth, maxdepth(root->children[i])); + depth = max (depth, maxDepth(root->children[i])); } return depth + 1; } @@ -247,15 +247,15 @@ public: ```CPP class solution { public: - int maxdepth(node* root) { - queue que; + int maxDepth(Node* root) { + queue que; if (root != NULL) que.push(root); int depth = 0; while (!que.empty()) { int size = que.size(); depth++; // 记录深度 for (int i = 0; i < size; i++) { - node* node = que.front(); + Node* node = que.front(); que.pop(); for (int j = 0; j < node->children.size(); j++) { if (node->children[j]) que.push(node->children[j]); From 7e80792a63f6d0b63745f2bb5c401b1a749afc1a Mon Sep 17 00:00:00 2001 From: YuZou Date: Fri, 31 Mar 2023 22:20:36 +0800 Subject: [PATCH 04/29] =?UTF-8?q?update=200045.=E8=B7=B3=E8=B7=83=E6=B8=B8?= =?UTF-8?q?=E6=88=8FII.md=20=E4=BF=AE=E6=94=B9=E7=AE=97=E6=B3=95=E9=87=8D?= =?UTF-8?q?=E5=A4=8D=E8=AF=AD=E4=B9=89?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0045.跳跃游戏II.md | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/problems/0045.跳跃游戏II.md b/problems/0045.跳跃游戏II.md index c6e4e9b5..2f6e8b67 100644 --- a/problems/0045.跳跃游戏II.md +++ b/problems/0045.跳跃游戏II.md @@ -76,11 +76,9 @@ public: for (int i = 0; i < nums.size(); i++) { nextDistance = max(nums[i] + i, nextDistance); // 更新下一步覆盖最远距离下标 if (i == curDistance) { // 遇到当前覆盖最远距离下标 - if (curDistance < nums.size() - 1) { // 如果当前覆盖最远距离下标不是终点 - ans++; // 需要走下一步 - curDistance = nextDistance; // 更新当前覆盖最远距离下标（相当于加油了） - if (nextDistance >= nums.size() - 1) break; // 下一步的覆盖范围已经可以达到终点，结束循环 - } else break; // 当前覆盖最远距到达集合终点，不用做ans++操作了，直接结束 + ans++; // 需要走下一步 + curDistance = nextDistance; // 更新当前覆盖最远距离下标（相当于加油了） + if (nextDistance >= nums.size() - 1) break; // 当前覆盖最远距到达集合终点，不用做ans++操作了，直接结束 } } return ans; From 6943358d8f75b4c189bcedaa5b79d5c0b0a93c2a Mon Sep 17 00:00:00 2001 From: ZerenZhang2022 <118794589+ZerenZhang2022@users.noreply.github.com> Date: Fri, 31 Mar 2023 21:58:27 -0400 Subject: [PATCH 05/29] =?UTF-8?q?Update=200538.=E6=8A=8A=E4=BA=8C=E5=8F=89?= =?UTF-8?q?=E6=90=9C=E7=B4=A2=E6=A0=91=E8=BD=AC=E6=8D=A2=E4=B8=BA=E7=B4=AF?= =?UTF-8?q?=E5=8A=A0=E6=A0=91.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 增加 python 迭代法 --- ...38.把二叉搜索树转换为累加树.md | 20 +++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/problems/0538.把二叉搜索树转换为累加树.md b/problems/0538.把二叉搜索树转换为累加树.md index 29b21840..ad5310e1 100644 --- a/problems/0538.把二叉搜索树转换为累加树.md +++ b/problems/0538.把二叉搜索树转换为累加树.md @@ -234,6 +234,26 @@ class Solution: return root ``` +**迭代** +```python +class Solution: + def convertBST(self, root: Optional[TreeNode]) -> Optional[TreeNode]: + if not root: return root + stack = [] + result = [] + cur = root + pre = 0 + while cur or stack: + if cur: + stack.append(cur) + cur = cur.right + else: + cur = stack.pop() + cur.val+= pre + pre = cur.val + cur =cur.left + return root +``` ## Go From ddda474eb4d73d894205cd5845b0c41f1b34226b Mon Sep 17 00:00:00 2001 From: fw_qaq Date: Sat, 1 Apr 2023 11:42:50 +0800 Subject: [PATCH 06/29] =?UTF-8?q?Update=200056.=E5=90=88=E5=B9=B6=E5=8C=BA?= =?UTF-8?q?=E9=97=B4.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0056.合并区间.md | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) diff --git a/problems/0056.合并区间.md b/problems/0056.合并区间.md index 17d2cc0a..d03a590d 100644 --- a/problems/0056.合并区间.md +++ b/problems/0056.合并区间.md @@ -280,24 +280,22 @@ object Solution { ```Rust impl Solution { - fn max(a: i32, b: i32) -> i32 { - if a > b { a } else { b } - } - - pub fn merge(intervals: Vec>) -> Vec> { - let mut intervals = intervals; - let mut result = Vec::new(); - if intervals.len() == 0 { return result; } - intervals.sort_by(|a, b| a[0].cmp(&b[0])); - result.push(intervals[0].clone()); - for i in 1..intervals.len() { - if result.last_mut().unwrap()[1] >= intervals[i][0] { - result.last_mut().unwrap()[1] = Self::max(result.last_mut().unwrap()[1], intervals[i][1]); + pub fn merge(mut intervals: Vec>) -> Vec> { + let mut res = vec![]; + if intervals.is_empty() { + return res; + } + intervals.sort_by_key(|a| a[0]); + res.push(intervals[0].clone()); + for interval in intervals.into_iter().skip(1) { + let res_last_ele = res.last_mut().unwrap(); + if res_last_ele[1] >= interval[0] { + res_last_ele[1] = interval[1].max(res_last_ele[1]); } else { - result.push(intervals[i].clone()); + res.push(interval); } } - result + res } } ``` From cd1a680c26c25e928b7a56f3e98ce8d00f7e1577 Mon Sep 17 00:00:00 2001 From: fw_qaq Date: Sat, 1 Apr 2023 12:22:37 +0800 Subject: [PATCH 07/29] =?UTF-8?q?Update=200738.=E5=8D=95=E8=B0=83=E9=80=92?= =?UTF-8?q?=E5=A2=9E=E7=9A=84=E6=95=B0=E5=AD=97.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0738.单调递增的数字.md | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/problems/0738.单调递增的数字.md b/problems/0738.单调递增的数字.md index f92652cd..1cf8a0a6 100644 --- a/problems/0738.单调递增的数字.md +++ b/problems/0738.单调递增的数字.md @@ -280,18 +280,20 @@ object Solution { ```Rust impl Solution { pub fn monotone_increasing_digits(n: i32) -> i32 { - let mut str_num = n.to_string().chars().map(|x| x.to_digit(10).unwrap() as i32).collect::>(); - let mut flag = str_num.len(); - for i in (1..str_num.len()).rev() { - if str_num[i - 1] > str_num[i] { + let mut n_bytes = n.to_string().into_bytes(); + let mut flag = n_bytes.len(); + for i in (1..n_bytes.len()).rev() { + if n_bytes[i - 1] > n_bytes[i] { flag = i; - str_num[i - 1] -= 1; + n_bytes[i - 1] -= 1; } } - for i in flag..str_num.len() { - str_num[i] = 9; + for v in n_bytes.iter_mut().skip(flag) { + *v = 57; } - str_num.iter().fold(0, |acc, x| acc * 10 + x) + n_bytes + .into_iter() + .fold(0, |acc, x| acc * 10 + x as i32 - 48) } } ``` From d7d7e6c733716a7eb516dea3c8b7660e8d0ac9ce Mon Sep 17 00:00:00 2001 From: ray Date: Sat, 1 Apr 2023 20:54:58 +0800 Subject: [PATCH 08/29] =?UTF-8?q?=E4=BF=AE=E6=94=B9=200203.=E7=A7=BB?= =?UTF-8?q?=E9=99=A4=E9=93=BE=E8=A1=A8=E5=85=83=E7=B4=A0.md=20=E5=86=99?= =?UTF-8?q?=E6=B3=95=E6=9B=B4Python=E4=B8=80=E7=82=B9?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0203.移除链表元素.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/problems/0203.移除链表元素.md b/problems/0203.移除链表元素.md index 7e3955a5..b52f16ea 100644 --- a/problems/0203.移除链表元素.md +++ b/problems/0203.移除链表元素.md @@ -316,8 +316,8 @@ 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): + while cur.next: + if cur.next.val == val: cur.next = cur.next.next #删除cur.next节点 else: cur = cur.next From befa14402bbf12eb147235e190bb775a42169ba9 Mon Sep 17 00:00:00 2001 From: jyu <1025368039@qq.com> Date: Sat, 1 Apr 2023 21:45:43 +0800 Subject: [PATCH 09/29] =?UTF-8?q?=E5=A2=9E=E5=8A=A0151=20C=E8=AF=AD?= =?UTF-8?q?=E8=A8=80=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0151.翻转字符串里的单词.md | 43 ++++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/problems/0151.翻转字符串里的单词.md b/problems/0151.翻转字符串里的单词.md index 1b006665..8fa7c77c 100644 --- a/problems/0151.翻转字符串里的单词.md +++ b/problems/0151.翻转字符串里的单词.md @@ -970,6 +970,49 @@ pub fn remove_extra_spaces(s: &mut Vec) { } } ``` +C: + +```C +// 翻转字符串中指定范围的字符 +void reverse(char* s, int start, int end) { + for (int i = start, j = end; i < j; i++, j--) { + int tmp = s[i]; + s[i] = s[j]; + s[j] = tmp; + } +} + +// 删除字符串两端和中间多余的空格 +void removeExtraSpace(char* s) { + int start = 0; // 指向字符串开头的指针 + int end = strlen(s) - 1; // 指向字符串结尾的指针 + while (s[start] == ' ') start++; // 移动指针 start，直到找到第一个非空格字符 + while (s[end] == ' ') end--; // 移动指针 end，直到找到第一个非空格字符 + int slow = 0; // 指向新字符串的下一个写入位置的指针 + for (int i = start; i <= end; i++) { // 遍历整个字符串 + if (s[i] == ' ' && s[i+1] == ' ') { // 如果当前字符是空格，并且下一个字符也是空格，则跳过 + continue; + } + s[slow] = s[i]; // 否则，将当前字符复制到新字符串的 slow 位置 + slow++; // 将 slow 指针向后移动 + } + s[slow] = '\0'; // 在新字符串的末尾添加一个空字符 +} + +// 翻转字符串中的单词 +char * reverseWords(char * s){ + removeExtraSpace(s); // 先删除字符串两端和中间的多余空格 + reverse(s, 0, strlen(s) - 1); // 翻转整个字符串 + int slow = 0; // 指向每个单词的开头位置的指针 + for (int i = 0; i <= strlen(s); i++) { // 遍历整个字符串 + if (s[i] ==' ' || s[i] == '\0') { // 如果当前字符是空格或空字符，说明一个单词结束了 + reverse(s, slow, i-1); // 翻转单词 + slow = i + 1; // 将 slow 指针指向下一个单词的开头位置 + } + } + return s; // 返回处理后的字符串 +} +```

From c1f17275e5879b94e0dcbc321f9dd434068ce516 Mon Sep 17 00:00:00 2001 From: mercer5 <602502833@qq.com> Date: Sun, 2 Apr 2023 11:40:30 +0800 Subject: [PATCH 10/29] =?UTF-8?q?=E6=B7=BB=E5=8A=A00739=E6=AF=8F=E6=97=A5?= =?UTF-8?q?=E6=B8=A9=E5=BA=A6=20python=20=E7=B2=BE=E7=AE=80=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/0739.每日温度.md | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/problems/0739.每日温度.md b/problems/0739.每日温度.md index 263a28f4..e521fbc6 100644 --- a/problems/0739.每日温度.md +++ b/problems/0739.每日温度.md @@ -271,6 +271,7 @@ class Solution { ``` Python： +> 未精简版本 ```python class Solution: @@ -291,6 +292,22 @@ class Solution: return answer ``` +> 精简版本 + +```python +class Solution: + def dailyTemperatures(self, temperatures: List[int]) -> List[int]: + # 单调栈 + answer = [0]*len(temperatures) + stack = [] + for i in range(len(temperatures)): + while len(stack)>0 and temperatures[i] > temperatures[stack[-1]]: + answer[stack[-1]] = i - stack[-1] + stack.pop() + stack.append(i) + return answer +``` + Go： > 暴力法 From a490e39206f4fd5d89165bbf0b38f982736e5309 Mon Sep 17 00:00:00 2001 From: mercer5 <602502833@qq.com> Date: Sun, 2 Apr 2023 11:50:29 +0800 Subject: [PATCH 11/29] =?UTF-8?q?=E4=BF=AE=E6=94=B90739=E6=AF=8F=E6=97=A5?= =?UTF-8?q?=E6=B8=A9=E5=BA=A6=20python=20=E7=B2=BE=E7=AE=80=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/0739.每日温度.md | 1 - 1 file changed, 1 deletion(-) diff --git a/problems/0739.每日温度.md b/problems/0739.每日温度.md index e521fbc6..749dc972 100644 --- a/problems/0739.每日温度.md +++ b/problems/0739.每日温度.md @@ -297,7 +297,6 @@ class Solution: ```python class Solution: def dailyTemperatures(self, temperatures: List[int]) -> List[int]: - # 单调栈 answer = [0]*len(temperatures) stack = [] for i in range(len(temperatures)): From 34e1b0ab5ce4a839ac9bf40b9e7ceb582fd51119 Mon Sep 17 00:00:00 2001 From: ayao98 <91120769+ayao98@users.noreply.github.com> Date: Mon, 3 Apr 2023 15:48:51 +0800 Subject: [PATCH 12/29] =?UTF-8?q?Update=200112.=E8=B7=AF=E5=BE=84=E6=80=BB?= =?UTF-8?q?=E5=92=8C.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0112.路径总和.md | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/problems/0112.路径总和.md b/problems/0112.路径总和.md index 9b6027d1..5958de93 100644 --- a/problems/0112.路径总和.md +++ b/problems/0112.路径总和.md @@ -250,7 +250,7 @@ private: vector> result; vector path; // 递归函数不需要返回值，因为我们要遍历整个树 - void traversal(treenode* cur, int count) { + void traversal(TreeNode* cur, int count) { if (!cur->left && !cur->right && count == 0) { // 遇到了叶子节点且找到了和为sum的路径 result.push_back(path); return; @@ -276,10 +276,10 @@ private: } public: - vector> pathsum(treenode* root, int sum) { + vector> pathSum(TreeNode* root, int sum) { result.clear(); path.clear(); - if (root == null) return result; + if (root == NULL) return result; path.push_back(root->val); // 把根节点放进路径 traversal(root, sum - root->val); return result; From 9e27f3dd9b40dabef0afd7e085fb6dec0e745474 Mon Sep 17 00:00:00 2001 From: ZerenZhang2022 <118794589+ZerenZhang2022@users.noreply.github.com> Date: Tue, 4 Apr 2023 22:51:45 -0400 Subject: [PATCH 13/29] =?UTF-8?q?Update=200332.=E9=87=8D=E6=96=B0=E5=AE=89?= =?UTF-8?q?=E6=8E=92=E8=A1=8C=E7=A8=8B.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 增加： python - 使用used数组 - 神似之前几题写法 --- problems/0332.重新安排行程.md | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/problems/0332.重新安排行程.md b/problems/0332.重新安排行程.md index 9bd5df7a..95e7d3ed 100644 --- a/problems/0332.重新安排行程.md +++ b/problems/0332.重新安排行程.md @@ -380,7 +380,33 @@ class Solution: backtracking("JFK") return path ``` + +python - 使用used数组 - 神似之前几题写法 +```python +class Solution: + def findItinerary(self, tickets: List[List[str]]) -> List[str]: + global used,path,results + used = [0]*len(tickets) + path = ['JFK'] + results = [] + tickets.sort() # 先排序，这样一旦找到第一个可行路径，一定是字母排序最小的 + self.backtracking(tickets,'JFK') + return results[0] + def backtracking(self,tickets,cur): + if sum(used) == len(tickets): + results.append(path[:]) + return True # 只要找到就返回 + for i in range(len(tickets)): + if tickets[i][0]==cur and used[i]==0: + used[i]=1 + path.append(tickets[i][1]) + state = self.backtracking(tickets,tickets[i][1]) + path.pop() + used[i]=0 + if state: return True # 只要找到就返回，不继续搜索了 +``` + ### GO ```go type pair struct { From 4e1590e26db6363af09e0feef0109d27d48b3958 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 11:14:10 +0800 Subject: [PATCH 14/29] =?UTF-8?q?update=20=200474.=E4=B8=80=E5=92=8C?= =?UTF-8?q?=E9=9B=B6=20=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D=E6=9D=82?= =?UTF-8?q?=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0474.一和零.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0474.一和零.md b/problems/0474.一和零.md index 8d79d701..6a178a25 100644 --- a/problems/0474.一和零.md +++ b/problems/0474.一和零.md @@ -156,6 +156,11 @@ public: }; ``` +* 时间复杂度: O(kmn)，k 为strs的长度 +* 空间复杂度: O(mn) + + + ## 总结 不少同学刷过这道题，可能没有总结这究竟是什么背包。 From f701133a9a8b418904cf02583e90d3c7fcbdd743 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 11:17:04 +0800 Subject: [PATCH 15/29] =?UTF-8?q?update=20=20=200518.=E9=9B=B6=E9=92=B1?= =?UTF-8?q?=E5=85=91=E6=8D=A2II=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D?= =?UTF-8?q?=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0518.零钱兑换II.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0518.零钱兑换II.md b/problems/0518.零钱兑换II.md index eb5a844c..c208754f 100644 --- a/problems/0518.零钱兑换II.md +++ b/problems/0518.零钱兑换II.md @@ -179,6 +179,11 @@ public: } }; ``` + +* 时间复杂度: O(mn)，其中 m 是amount，n 是 coins 的长度 +* 空间复杂度: O(m) + + 是不是发现代码如此精简，哈哈 ## 总结 From 6e62049cd3f06e5bf156240087d90bdfb5910569 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 11:20:07 +0800 Subject: [PATCH 16/29] =?UTF-8?q?update=20=200377.=E7=BB=84=E5=90=88?= =?UTF-8?q?=E6=80=BB=E5=92=8C=E2=85=A3=20=EF=BC=9A=E6=B7=BB=E5=8A=A0?= =?UTF-8?q?=E5=A4=8D=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0377.组合总和Ⅳ.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0377.组合总和Ⅳ.md b/problems/0377.组合总和Ⅳ.md index f2287188..ee659723 100644 --- a/problems/0377.组合总和Ⅳ.md +++ b/problems/0377.组合总和Ⅳ.md @@ -130,6 +130,11 @@ public: ``` +* 时间复杂度: O(target * n)，其中 n 为 nums 的长度 +* 空间复杂度: O(target) + + + C++测试用例有两个数相加超过int的数据，所以需要在if里加上dp[i] < INT_MAX - dp[i - num]。 但java就不用考虑这个限制，java里的int也是四个字节吧，也有可能leetcode后台对不同语言的测试数据不一样。 From 84b84e5bf11158c3ab4ac2356c8290060b7ebf45 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 11:46:51 +0800 Subject: [PATCH 17/29] =?UTF-8?q?update=20=20=200070.=E7=88=AC=E6=A5=BC?= =?UTF-8?q?=E6=A2=AF=E5=AE=8C=E5=85=A8=E8=83=8C=E5=8C=85=E7=89=88=E6=9C=AC?= =?UTF-8?q?=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D=E6=9D=82=E5=BA=A6=E5=88=86?= =?UTF-8?q?=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0070.爬楼梯完全背包版本.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0070.爬楼梯完全背包版本.md b/problems/0070.爬楼梯完全背包版本.md index 41c2e616..8f8bc9a6 100644 --- a/problems/0070.爬楼梯完全背包版本.md +++ b/problems/0070.爬楼梯完全背包版本.md @@ -101,6 +101,11 @@ public: }; ``` +* 时间复杂度: O(nm) +* 空间复杂度: O(n) + + + 代码中m表示最多可以爬m个台阶，代码中把m改成2就是本题70.爬楼梯可以AC的代码了。 ## 总结 From 9fef5cbd00bde88126d4407c913d4b5f448d5308 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 11:51:41 +0800 Subject: [PATCH 18/29] =?UTF-8?q?=20update=20=20=200322.=E9=9B=B6=E9=92=B1?= =?UTF-8?q?=E5=85=91=E6=8D=A2=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D=E6=9D=82?= =?UTF-8?q?=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0322.零钱兑换.md | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/problems/0322.零钱兑换.md b/problems/0322.零钱兑换.md index 3be72565..0e3947da 100644 --- a/problems/0322.零钱兑换.md +++ b/problems/0322.零钱兑换.md @@ -133,6 +133,11 @@ public: }; ``` +* 时间复杂度: O(n * amount)，其中 n 为 coins 的长度 +* 空间复杂度: O(amount) + + + 对于遍历方式遍历背包放在外循环，遍历物品放在内循环也是可以的，我就直接给出代码了 ```CPP @@ -154,6 +159,8 @@ public: } }; ``` +* 同上 + ## 总结 From b6fcdc160d85cd5d541c851f514e7ea332ffd4b4 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 11:57:47 +0800 Subject: [PATCH 19/29] =?UTF-8?q?=20update=20=20=200279.=E5=AE=8C=E5=85=A8?= =?UTF-8?q?=E5=B9=B3=E6=96=B9=E6=95=B0=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D?= =?UTF-8?q?=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0279.完全平方数.md | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/problems/0279.完全平方数.md b/problems/0279.完全平方数.md index c329156b..f5b23d26 100644 --- a/problems/0279.完全平方数.md +++ b/problems/0279.完全平方数.md @@ -127,6 +127,10 @@ public: }; ``` +* 时间复杂度: O(n * √n) +* 空间复杂度: O(n) + + 同样我在给出先遍历物品，在遍历背包的代码，一样的可以AC的。 ```CPP @@ -145,6 +149,8 @@ public: } }; ``` +* 同上 + ## 总结 From ecf8251c6ad8c3524ebbe282a62a682acc91824b Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 13:58:53 +0800 Subject: [PATCH 20/29] =?UTF-8?q?update=20=20=200198.=E6=89=93=E5=AE=B6?= =?UTF-8?q?=E5=8A=AB=E8=88=8D=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D=E6=9D=82?= =?UTF-8?q?=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0198.打家劫舍.md | 3 +++ 1 file changed, 3 insertions(+) diff --git a/problems/0198.打家劫舍.md b/problems/0198.打家劫舍.md index fdb2dabf..c25f3b86 100644 --- a/problems/0198.打家劫舍.md +++ b/problems/0198.打家劫舍.md @@ -108,6 +108,9 @@ public: }; ``` +* 时间复杂度: O(n) +* 空间复杂度: O(n) + ## 总结 打家劫舍是DP解决的经典题目，这道题也是打家劫舍入门级题目，后面我们还会变种方式来打劫的。 From 6754a955688dd80870593da89fa26d889074e748 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:00:01 +0800 Subject: [PATCH 21/29] =?UTF-8?q?update=20=200213.=E6=89=93=E5=AE=B6?= =?UTF-8?q?=E5=8A=AB=E8=88=8DII=20=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D?= =?UTF-8?q?=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0213.打家劫舍II.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0213.打家劫舍II.md b/problems/0213.打家劫舍II.md index 0627eedb..becad069 100644 --- a/problems/0213.打家劫舍II.md +++ b/problems/0213.打家劫舍II.md @@ -82,6 +82,11 @@ public: }; ``` +* 时间复杂度: O(n) +* 空间复杂度: O(n) + + + ## 总结 成环之后还是难了一些的， 不少题解没有把“考虑房间”和“偷房间”说清楚。 From 56b35274356fe0cecda151e5d1aa77a9f8b750b3 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:07:01 +0800 Subject: [PATCH 22/29] =?UTF-8?q?update=20=200188.=E4=B9=B0=E5=8D=96?= =?UTF-8?q?=E8=82=A1=E7=A5=A8=E7=9A=84=E6=9C=80=E4=BD=B3=E6=97=B6=E6=9C=BA?= =?UTF-8?q?IV=20=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D=E6=9D=82=E5=BA=A6?= =?UTF-8?q?=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0188.买卖股票的最佳时机IV.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0188.买卖股票的最佳时机IV.md b/problems/0188.买卖股票的最佳时机IV.md index 4fdd7bf4..f6744a2b 100644 --- a/problems/0188.买卖股票的最佳时机IV.md +++ b/problems/0188.买卖股票的最佳时机IV.md @@ -156,6 +156,11 @@ public: }; ``` +* 时间复杂度: O(n * k)，其中 n 为 prices 的长度 +* 空间复杂度: O(n * k) + + + 当然有的解法是定义一个三维数组dp[i][j][k]，第i天，第j次买卖，k表示买还是卖的状态，从定义上来讲是比较直观。 但感觉三维数组操作起来有些麻烦，我是直接用二维数组来模拟三维数组的情况，代码看起来也清爽一些。 From 5bc0fa5c96684068bec235ca353e297b199f5414 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:08:42 +0800 Subject: [PATCH 23/29] =?UTF-8?q?=20update=20=20=200300.=E6=9C=80=E9=95=BF?= =?UTF-8?q?=E4=B8=8A=E5=8D=87=E5=AD=90=E5=BA=8F=E5=88=97=EF=BC=9A=E6=B7=BB?= =?UTF-8?q?=E5=8A=A0=E5=A4=8D=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0300.最长上升子序列.md | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/problems/0300.最长上升子序列.md b/problems/0300.最长上升子序列.md index 478837cc..e8cb0b5f 100644 --- a/problems/0300.最长上升子序列.md +++ b/problems/0300.最长上升子序列.md @@ -106,6 +106,10 @@ public: } }; ``` +* 时间复杂度: O(n^2) +* 空间复杂度: O(n) + + ## 总结 From 1ed179e233bc18574a3f4e7b46cbbed9ab686667 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:11:04 +0800 Subject: [PATCH 24/29] =?UTF-8?q?update=20=20=201143.=E6=9C=80=E9=95=BF?= =?UTF-8?q?=E5=85=AC=E5=85=B1=E5=AD=90=E5=BA=8F=E5=88=97=EF=BC=9A=E6=B7=BB?= =?UTF-8?q?=E5=8A=A0=E5=A4=8D=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/1143.最长公共子序列.md | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/problems/1143.最长公共子序列.md b/problems/1143.最长公共子序列.md index 8e5f7eb2..730e9ad1 100644 --- a/problems/1143.最长公共子序列.md +++ b/problems/1143.最长公共子序列.md @@ -124,6 +124,10 @@ public: } }; ``` +* 时间复杂度: O(n * m)，其中 n 和 m 分别为 text1 和 text2 的长度 +* 空间复杂度: O(n * m) + + ## 其他语言版本 From 4ded4b5c820f3098ab54a3dbd6cda23e0c5e70ff Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:12:41 +0800 Subject: [PATCH 25/29] =?UTF-8?q?update=20=20=201035.=E4=B8=8D=E7=9B=B8?= =?UTF-8?q?=E4=BA=A4=E7=9A=84=E7=BA=BF=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D?= =?UTF-8?q?=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/1035.不相交的线.md | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/problems/1035.不相交的线.md b/problems/1035.不相交的线.md index d1e1e30a..7b60abdd 100644 --- a/problems/1035.不相交的线.md +++ b/problems/1035.不相交的线.md @@ -62,6 +62,10 @@ public: } }; ``` +* 时间复杂度: O(n * m) +* 空间复杂度: O(n * m) + + ## 总结 From f579a9f82e89f18338b7af64f94e76a63fa7f96d Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:14:03 +0800 Subject: [PATCH 26/29] =?UTF-8?q?update=20=20=200115.=E4=B8=8D=E5=90=8C?= =?UTF-8?q?=E7=9A=84=E5=AD=90=E5=BA=8F=E5=88=97=EF=BC=9A=E6=B7=BB=E5=8A=A0?= =?UTF-8?q?=E5=A4=8D=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0115.不同的子序列.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0115.不同的子序列.md b/problems/0115.不同的子序列.md index daa708bc..6127f190 100644 --- a/problems/0115.不同的子序列.md +++ b/problems/0115.不同的子序列.md @@ -149,6 +149,11 @@ public: }; ``` +* 时间复杂度: O(n * m) +* 空间复杂度: O(n * m) + + + ## 其他语言版本 From 7d6476c16a421ef03c56ee101e1fd16b1d47ea9c Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:15:40 +0800 Subject: [PATCH 27/29] =?UTF-8?q?update=20=200583.=E4=B8=A4=E4=B8=AA?= =?UTF-8?q?=E5=AD=97=E7=AC=A6=E4=B8=B2=E7=9A=84=E5=88=A0=E9=99=A4=E6=93=8D?= =?UTF-8?q?=E4=BD=9C=20=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D=E6=9D=82?= =?UTF-8?q?=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0583.两个字符串的删除操作.md | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/problems/0583.两个字符串的删除操作.md b/problems/0583.两个字符串的删除操作.md index eb046a9d..561ad2f2 100644 --- a/problems/0583.两个字符串的删除操作.md +++ b/problems/0583.两个字符串的删除操作.md @@ -104,6 +104,10 @@ public: }; ``` +* 时间复杂度: O(n * m) +* 空间复杂度: O(n * m) + + ### 动态规划二 @@ -127,6 +131,10 @@ public: }; ``` +* 时间复杂度: O(n * m) +* 空间复杂度: O(n * m) + + ## 其他语言版本 From 541ac6ef3cfe7da2312df2cedf9df63edce2b325 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:16:43 +0800 Subject: [PATCH 28/29] =?UTF-8?q?update=20=20=200072.=E7=BC=96=E8=BE=91?= =?UTF-8?q?=E8=B7=9D=E7=A6=BB=EF=BC=9A=E6=B7=BB=E5=8A=A0=E5=A4=8D=E6=9D=82?= =?UTF-8?q?=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0072.编辑距离.md | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/problems/0072.编辑距离.md b/problems/0072.编辑距离.md index 0b49e3c6..cc4ab00c 100644 --- a/problems/0072.编辑距离.md +++ b/problems/0072.编辑距离.md @@ -218,6 +218,10 @@ public: } }; ``` +* 时间复杂度: O(n * m) +* 空间复杂度: O(n * m) + + ## 其他语言版本 From a26fe0fdf4559c535ac3f04d4e43e87b86b01196 Mon Sep 17 00:00:00 2001 From: Yuhao Ju Date: Tue, 11 Apr 2023 14:17:50 +0800 Subject: [PATCH 29/29] =?UTF-8?q?update=20=200516.=E6=9C=80=E9=95=BF?= =?UTF-8?q?=E5=9B=9E=E6=96=87=E5=AD=90=E5=BA=8F=E5=88=97=20=EF=BC=9A?= =?UTF-8?q?=E6=B7=BB=E5=8A=A0=E5=A4=8D=E6=9D=82=E5=BA=A6=E5=88=86=E6=9E=90?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0516.最长回文子序列.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0516.最长回文子序列.md b/problems/0516.最长回文子序列.md index d28a33cc..fcdd57b0 100644 --- a/problems/0516.最长回文子序列.md +++ b/problems/0516.最长回文子序列.md @@ -144,6 +144,11 @@ public: } }; ``` +* 时间复杂度: O(n^2) +* 空间复杂度: O(n^2) + + + ## 其他语言版本