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Commit edc2ea8

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feat: update solutions to lcci problem: No.02.05 (doocs#2322)
No.02.05.Sum Lists
1 parent 1ab2686 commit edc2ea8

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‎lcci/02.05.Sum Lists/README.md‎

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## 解法
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### 方法一
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### 方法一:模拟
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我们同时遍历两个链表 $l_1$ 和 $l_2,ドル并使用变量 $carry$ 表示当前是否有进位。
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每次遍历时,我们取出对应链表的当前位,计算它们与进位 $carry$ 的和,然后更新进位的值,最后将当前位的值加入答案链表。如果两个链表都遍历完了,并且进位为 0ドル$ 时,遍历结束。
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最后我们返回答案链表的头节点即可。
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时间复杂度 $O(\max(m, n)),ドル其中 $m$ 和 $n$ 分别为两个链表的长度。我们需要遍历两个链表的全部位置,而处理每个位置只需要 $O(1)$ 的时间。忽略答案的空间消耗,空间复杂度 $O(1)$。
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<!-- tabs:start -->
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class Solution:
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def addTwoNumbers(self, l1: ListNode, l2: ListNode) -> ListNode:
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dummy = cur =ListNode(0)
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carry= 0
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dummy = ListNode()
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carry, curr = 0, dummy
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while l1 or l2 or carry:
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carry += (0 if notl1 else l1.val) + (0 if notl2 else l2.val)
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cur.next = ListNode(carry % 10)
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cur = cur.next
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carry //=10
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l1 = None if notl1 else l1.next
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l2 = None if notl2 else l2.next
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s = (l1.val if l1 else 0) + (l2.val if l2 else 0) + carry
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carry, val =divmod(s, 10)
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curr.next = ListNode(val)
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curr = curr.next
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l1 = l1.next if l1 else None
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l2 = l2.next if l2 else None
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return dummy.next
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```
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@@ -66,8 +74,8 @@ class Solution:
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*/
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class Solution {
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public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
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ListNode dummy = new ListNode(0);
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int carry = 0;
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ListNode dummy = new ListNode(-1);
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ListNode cur = dummy;
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while (l1 != null || l2 != null || carry != 0) {
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int s = (l1 == null ? 0 : l1.val) + (l2 == null ? 0 : l2.val) + carry;

‎lcci/02.05.Sum Lists/README_EN.md‎

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## Solutions
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### Solution 1
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### Solution 1: Simulation
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We traverse two linked lists $l_1$ and $l_2$ simultaneously, and use a variable $carry$ to indicate whether there is a carry-over currently.
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During each traversal, we take out the current digit of the corresponding linked list, calculate the sum of them and the carry-over $carry,ドル then update the value of the carry-over, and finally add the value of the current digit to the answer linked list. The traversal ends when both linked lists have been traversed and the carry-over is 0ドル$.
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Finally, we return the head node of the answer linked list.
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The time complexity is $O(\max(m, n)),ドル where $m$ and $n$ are the lengths of the two linked lists respectively. We need to traverse all positions of the two linked lists, and it only takes $O(1)$ time to process each position. Ignoring the space consumption of the answer, the space complexity is $O(1)$.
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<!-- tabs:start -->
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class Solution:
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def addTwoNumbers(self, l1: ListNode, l2: ListNode) -> ListNode:
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dummy = cur =ListNode(0)
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carry= 0
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dummy = ListNode()
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carry, curr = 0, dummy
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while l1 or l2 or carry:
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carry += (0 if notl1 else l1.val) + (0 if notl2 else l2.val)
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cur.next = ListNode(carry % 10)
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cur = cur.next
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carry //=10
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l1 = None if notl1 else l1.next
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l2 = None if notl2 else l2.next
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s = (l1.val if l1 else 0) + (l2.val if l2 else 0) + carry
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carry, val =divmod(s, 10)
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curr.next = ListNode(val)
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curr = curr.next
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l1 = l1.next if l1 else None
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l2 = l2.next if l2 else None
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return dummy.next
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```
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@@ -69,8 +77,8 @@ class Solution:
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*/
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class Solution {
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public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
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ListNode dummy = new ListNode(0);
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int carry = 0;
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ListNode dummy = new ListNode(-1);
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ListNode cur = dummy;
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while (l1 != null || l2 != null || carry != 0) {
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int s = (l1 == null ? 0 : l1.val) + (l2 == null ? 0 : l2.val) + carry;

‎lcci/02.05.Sum Lists/Solution.java‎

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Original file line numberDiff line numberDiff line change
@@ -8,8 +8,8 @@
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*/
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class Solution {
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public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
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ListNode dummy = new ListNode(0);
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int carry = 0;
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ListNode dummy = new ListNode(-1);
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ListNode cur = dummy;
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while (l1 != null || l2 != null || carry != 0) {
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int s = (l1 == null ? 0 : l1.val) + (l2 == null ? 0 : l2.val) + carry;

‎lcci/02.05.Sum Lists/Solution.py‎

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Original file line numberDiff line numberDiff line change
@@ -7,13 +7,13 @@
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class Solution:
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def addTwoNumbers(self, l1: ListNode, l2: ListNode) -> ListNode:
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dummy = cur=ListNode(0)
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carry= 0
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dummy = ListNode()
11+
carry, curr= 0, dummy
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while l1 or l2 or carry:
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carry+= (0 if notl1 else l1.val) + (0 if notl2 else l2.val)
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cur.next=ListNode(carry% 10)
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cur = cur.next
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carry//=10
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l1 = None if notl1 else l1.next
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l2 = None if notl2 else l2.next
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s= (l1.val if l1 else 0) + (l2.val if l2 else 0) +carry
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carry, val=divmod(s, 10)
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curr.next = ListNode(val)
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curr=curr.next
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l1 = l1.next if l1 else None
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l2 = l2.next if l2 else None
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return dummy.next

‎solution/README.md‎

Lines changed: 10 additions & 10 deletions
Original file line numberDiff line numberDiff line change
@@ -3014,7 +3014,7 @@
30143014
| 3001 | [捕获黑皇后需要的最少移动次数](/solution/3000-3099/3001.Minimum%20Moves%20to%20Capture%20The%20Queen/README.md) | `数组`,`枚举` | 中等 | 第 379 场周赛 |
30153015
| 3002 | [移除后集合的最多元素数](/solution/3000-3099/3002.Maximum%20Size%20of%20a%20Set%20After%20Removals/README.md) | `贪心`,`数组`,`哈希表` | 中等 | 第 379 场周赛 |
30163016
| 3003 | [执行操作后的最大分割数量](/solution/3000-3099/3003.Maximize%20the%20Number%20of%20Partitions%20After%20Operations/README.md) | `位运算`,`字符串`,`动态规划`,`状态压缩` | 困难 | 第 379 场周赛 |
3017-
| 3004 | [相同颜色的最大子树](/solution/3000-3099/3004.Maximum%20Subtree%20of%20the%20Same%20Color/README.md) | `树`,`深度优先搜索`,`数组` | 中等 | 🔒 |
3017+
| 3004 | [相同颜色的最大子树](/solution/3000-3099/3004.Maximum%20Subtree%20of%20the%20Same%20Color/README.md) | `树`,`深度优先搜索`,`数组`,`动态规划` | 中等 | 🔒 |
30183018
| 3005 | [最大频率元素计数](/solution/3000-3099/3005.Count%20Elements%20With%20Maximum%20Frequency/README.md) | `数组`,`哈希表`,`计数` | 简单 | 第 380 场周赛 |
30193019
| 3006 | [找出数组中的美丽下标 I](/solution/3000-3099/3006.Find%20Beautiful%20Indices%20in%20the%20Given%20Array%20I/README.md) | `双指针`,`字符串`,`二分查找`,`字符串匹配`,`哈希函数`,`滚动哈希` | 中等 | 第 380 场周赛 |
30203020
| 3007 | [价值和小于等于 K 的最大数字](/solution/3000-3099/3007.Maximum%20Number%20That%20Sum%20of%20the%20Prices%20Is%20Less%20Than%20or%20Equal%20to%20K/README.md) | `位运算`,`二分查找`,`动态规划` | 中等 | 第 380 场周赛 |
@@ -3033,15 +3033,15 @@
30333033
| 3020 | [子集中元素的最大数量](/solution/3000-3099/3020.Find%20the%20Maximum%20Number%20of%20Elements%20in%20Subset/README.md) | `数组`,`哈希表`,`枚举` | 中等 | 第 382 场周赛 |
30343034
| 3021 | [Alice 和 Bob 玩鲜花游戏](/solution/3000-3099/3021.Alice%20and%20Bob%20Playing%20Flower%20Game/README.md) | `数学` | 中等 | 第 382 场周赛 |
30353035
| 3022 | [给定操作次数内使剩余元素的或值最小](/solution/3000-3099/3022.Minimize%20OR%20of%20Remaining%20Elements%20Using%20Operations/README.md) | `贪心`,`位运算`,`数组` | 困难 | 第 382 场周赛 |
3036-
| 3023 | [在无限流中寻找模式 I](/solution/3000-3099/3023.Find%20Pattern%20in%20Infinite%20Stream%20I/README.md) | | 中等 | 🔒 |
3037-
| 3024 | [三角形类型 II](/solution/3000-3099/3024.Type%20of%20Triangle%20II/README.md) | | 简单 | 第 123 场双周赛 |
3038-
| 3025 | [人员站位的方案数 I](/solution/3000-3099/3025.Find%20the%20Number%20of%20Ways%20to%20Place%20People%20I/README.md) | | 中等 | 第 123 场双周赛 |
3039-
| 3026 | [最大好子数组和](/solution/3000-3099/3026.Maximum%20Good%20Subarray%20Sum/README.md) | | 中等 | 第 123 场双周赛 |
3040-
| 3027 | [人员站位的方案数 II](/solution/3000-3099/3027.Find%20the%20Number%20of%20Ways%20to%20Place%20People%20II/README.md) | | 困难 | 第 123 场双周赛 |
3041-
| 3028 | [边界上的蚂蚁](/solution/3000-3099/3028.Ant%20on%20the%20Boundary/README.md) | | 简单 | 第 383 场周赛 |
3042-
| 3029 | [将单词恢复初始状态所需的最短时间 I](/solution/3000-3099/3029.Minimum%20Time%20to%20Revert%20Word%20to%20Initial%20State%20I/README.md) | | 中等 | 第 383 场周赛 |
3043-
| 3030 | [找出网格的区域平均强度](/solution/3000-3099/3030.Find%20the%20Grid%20of%20Region%20Average/README.md) | | 中等 | 第 383 场周赛 |
3044-
| 3031 | [将单词恢复初始状态所需的最短时间 II](/solution/3000-3099/3031.Minimum%20Time%20to%20Revert%20Word%20to%20Initial%20State%20II/README.md) | | 困难 | 第 383 场周赛 |
3036+
| 3023 | [在无限流中寻找模式 I](/solution/3000-3099/3023.Find%20Pattern%20in%20Infinite%20Stream%20I/README.md) | `数组`,`字符串`,`字符串匹配`,`滑动窗口` | 中等 | 🔒 |
3037+
| 3024 | [三角形类型 II](/solution/3000-3099/3024.Type%20of%20Triangle%20II/README.md) | `数组`,`数学`,`排序` | 简单 | 第 123 场双周赛 |
3038+
| 3025 | [人员站位的方案数 I](/solution/3000-3099/3025.Find%20the%20Number%20of%20Ways%20to%20Place%20People%20I/README.md) | `几何`,`数组`,`数学`,`枚举`,`排序` | 中等 | 第 123 场双周赛 |
3039+
| 3026 | [最大好子数组和](/solution/3000-3099/3026.Maximum%20Good%20Subarray%20Sum/README.md) | `数组`,`哈希表`,`前缀和` | 中等 | 第 123 场双周赛 |
3040+
| 3027 | [人员站位的方案数 II](/solution/3000-3099/3027.Find%20the%20Number%20of%20Ways%20to%20Place%20People%20II/README.md) | `几何`,`数组`,`数学`,`枚举`,`排序` | 困难 | 第 123 场双周赛 |
3041+
| 3028 | [边界上的蚂蚁](/solution/3000-3099/3028.Ant%20on%20the%20Boundary/README.md) | `数组`,`前缀和`,`模拟` | 简单 | 第 383 场周赛 |
3042+
| 3029 | [将单词恢复初始状态所需的最短时间 I](/solution/3000-3099/3029.Minimum%20Time%20to%20Revert%20Word%20to%20Initial%20State%20I/README.md) | `字符串`,`字符串匹配`,`哈希函数`,`滚动哈希` | 中等 | 第 383 场周赛 |
3043+
| 3030 | [找出网格的区域平均强度](/solution/3000-3099/3030.Find%20the%20Grid%20of%20Region%20Average/README.md) | `数组`,`矩阵` | 中等 | 第 383 场周赛 |
3044+
| 3031 | [将单词恢复初始状态所需的最短时间 II](/solution/3000-3099/3031.Minimum%20Time%20to%20Revert%20Word%20to%20Initial%20State%20II/README.md) | `字符串`,`字符串匹配`,`哈希函数`,`滚动哈希` | 困难 | 第 383 场周赛 |
30453045

30463046
## 版权
30473047

‎solution/README_EN.md‎

Lines changed: 10 additions & 10 deletions
Original file line numberDiff line numberDiff line change
@@ -3012,7 +3012,7 @@ Press <kbd>Control</kbd> + <kbd>F</kbd>(or <kbd>Command</kbd> + <kbd>F</kbd> on
30123012
| 3001 | [Minimum Moves to Capture The Queen](/solution/3000-3099/3001.Minimum%20Moves%20to%20Capture%20The%20Queen/README_EN.md) | `Array`,`Enumeration` | Medium | Weekly Contest 379 |
30133013
| 3002 | [Maximum Size of a Set After Removals](/solution/3000-3099/3002.Maximum%20Size%20of%20a%20Set%20After%20Removals/README_EN.md) | `Greedy`,`Array`,`Hash Table` | Medium | Weekly Contest 379 |
30143014
| 3003 | [Maximize the Number of Partitions After Operations](/solution/3000-3099/3003.Maximize%20the%20Number%20of%20Partitions%20After%20Operations/README_EN.md) | `Bit Manipulation`,`String`,`Dynamic Programming`,`Bitmask` | Hard | Weekly Contest 379 |
3015-
| 3004 | [Maximum Subtree of the Same Color](/solution/3000-3099/3004.Maximum%20Subtree%20of%20the%20Same%20Color/README_EN.md) | `Tree`,`Depth-First Search`,`Array` | Medium | 🔒 |
3015+
| 3004 | [Maximum Subtree of the Same Color](/solution/3000-3099/3004.Maximum%20Subtree%20of%20the%20Same%20Color/README_EN.md) | `Tree`,`Depth-First Search`,`Array`,`Dynamic Programming` | Medium | 🔒 |
30163016
| 3005 | [Count Elements With Maximum Frequency](/solution/3000-3099/3005.Count%20Elements%20With%20Maximum%20Frequency/README_EN.md) | `Array`,`Hash Table`,`Counting` | Easy | Weekly Contest 380 |
30173017
| 3006 | [Find Beautiful Indices in the Given Array I](/solution/3000-3099/3006.Find%20Beautiful%20Indices%20in%20the%20Given%20Array%20I/README_EN.md) | `Two Pointers`,`String`,`Binary Search`,`String Matching`,`Hash Function`,`Rolling Hash` | Medium | Weekly Contest 380 |
30183018
| 3007 | [Maximum Number That Sum of the Prices Is Less Than or Equal to K](/solution/3000-3099/3007.Maximum%20Number%20That%20Sum%20of%20the%20Prices%20Is%20Less%20Than%20or%20Equal%20to%20K/README_EN.md) | `Bit Manipulation`,`Binary Search`,`Dynamic Programming` | Medium | Weekly Contest 380 |
@@ -3031,15 +3031,15 @@ Press <kbd>Control</kbd> + <kbd>F</kbd>(or <kbd>Command</kbd> + <kbd>F</kbd> on
30313031
| 3020 | [Find the Maximum Number of Elements in Subset](/solution/3000-3099/3020.Find%20the%20Maximum%20Number%20of%20Elements%20in%20Subset/README_EN.md) | `Array`,`Hash Table`,`Enumeration` | Medium | Weekly Contest 382 |
30323032
| 3021 | [Alice and Bob Playing Flower Game](/solution/3000-3099/3021.Alice%20and%20Bob%20Playing%20Flower%20Game/README_EN.md) | `Math` | Medium | Weekly Contest 382 |
30333033
| 3022 | [Minimize OR of Remaining Elements Using Operations](/solution/3000-3099/3022.Minimize%20OR%20of%20Remaining%20Elements%20Using%20Operations/README_EN.md) | `Greedy`,`Bit Manipulation`,`Array` | Hard | Weekly Contest 382 |
3034-
| 3023 | [Find Pattern in Infinite Stream I](/solution/3000-3099/3023.Find%20Pattern%20in%20Infinite%20Stream%20I/README_EN.md) | | Medium | 🔒 |
3035-
| 3024 | [Type of Triangle II](/solution/3000-3099/3024.Type%20of%20Triangle%20II/README_EN.md) | | Easy | Biweekly Contest 123 |
3036-
| 3025 | [Find the Number of Ways to Place People I](/solution/3000-3099/3025.Find%20the%20Number%20of%20Ways%20to%20Place%20People%20I/README_EN.md) | | Medium | Biweekly Contest 123 |
3037-
| 3026 | [Maximum Good Subarray Sum](/solution/3000-3099/3026.Maximum%20Good%20Subarray%20Sum/README_EN.md) | | Medium | Biweekly Contest 123 |
3038-
| 3027 | [Find the Number of Ways to Place People II](/solution/3000-3099/3027.Find%20the%20Number%20of%20Ways%20to%20Place%20People%20II/README_EN.md) | | Hard | Biweekly Contest 123 |
3039-
| 3028 | [Ant on the Boundary](/solution/3000-3099/3028.Ant%20on%20the%20Boundary/README_EN.md) | | Easy | Weekly Contest 383 |
3040-
| 3029 | [Minimum Time to Revert Word to Initial State I](/solution/3000-3099/3029.Minimum%20Time%20to%20Revert%20Word%20to%20Initial%20State%20I/README_EN.md) | | Medium | Weekly Contest 383 |
3041-
| 3030 | [Find the Grid of Region Average](/solution/3000-3099/3030.Find%20the%20Grid%20of%20Region%20Average/README_EN.md) | | Medium | Weekly Contest 383 |
3042-
| 3031 | [Minimum Time to Revert Word to Initial State II](/solution/3000-3099/3031.Minimum%20Time%20to%20Revert%20Word%20to%20Initial%20State%20II/README_EN.md) | | Hard | Weekly Contest 383 |
3034+
| 3023 | [Find Pattern in Infinite Stream I](/solution/3000-3099/3023.Find%20Pattern%20in%20Infinite%20Stream%20I/README_EN.md) | `Array`,`String`,`String Matching`,`Sliding Window` | Medium | 🔒 |
3035+
| 3024 | [Type of Triangle II](/solution/3000-3099/3024.Type%20of%20Triangle%20II/README_EN.md) | `Array`,`Math`,`Sorting` | Easy | Biweekly Contest 123 |
3036+
| 3025 | [Find the Number of Ways to Place People I](/solution/3000-3099/3025.Find%20the%20Number%20of%20Ways%20to%20Place%20People%20I/README_EN.md) | `Geometry`,`Array`,`Math`,`Enumeration`,`Sorting` | Medium | Biweekly Contest 123 |
3037+
| 3026 | [Maximum Good Subarray Sum](/solution/3000-3099/3026.Maximum%20Good%20Subarray%20Sum/README_EN.md) | `Array`,`Hash Table`,`Prefix Sum` | Medium | Biweekly Contest 123 |
3038+
| 3027 | [Find the Number of Ways to Place People II](/solution/3000-3099/3027.Find%20the%20Number%20of%20Ways%20to%20Place%20People%20II/README_EN.md) | `Geometry`,`Array`,`Math`,`Enumeration`,`Sorting` | Hard | Biweekly Contest 123 |
3039+
| 3028 | [Ant on the Boundary](/solution/3000-3099/3028.Ant%20on%20the%20Boundary/README_EN.md) | `Array`,`Prefix Sum`,`Simulation` | Easy | Weekly Contest 383 |
3040+
| 3029 | [Minimum Time to Revert Word to Initial State I](/solution/3000-3099/3029.Minimum%20Time%20to%20Revert%20Word%20to%20Initial%20State%20I/README_EN.md) | `String`,`String Matching`,`Hash Function`,`Rolling Hash` | Medium | Weekly Contest 383 |
3041+
| 3030 | [Find the Grid of Region Average](/solution/3000-3099/3030.Find%20the%20Grid%20of%20Region%20Average/README_EN.md) | `Array`,`Matrix` | Medium | Weekly Contest 383 |
3042+
| 3031 | [Minimum Time to Revert Word to Initial State II](/solution/3000-3099/3031.Minimum%20Time%20to%20Revert%20Word%20to%20Initial%20State%20II/README_EN.md) | `String`,`String Matching`,`Hash Function`,`Rolling Hash` | Hard | Weekly Contest 383 |
30433043

30443044
## Copyright
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