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Given the root of a binary tree and an integer targetSum, return the number of paths where the sum of the values along the path equals targetSum.

1796D. Maximum Subarray

Posted on 2024-06-02 Edited on 2025-06-14 In Leetcode

D. Maximum Subarray

Description

输入 T(≤1e4) 表示 T 组数据。所有数据的 n 之和 ≤2e5。
每组数据输入 n(1≤n≤2e5) k(0≤k≤min(20,n)) x(-1e9≤x≤1e9) 和长为 n 的数组 a(-1e9≤a[i]≤1e9)。

1843E. Tracking Segments

Posted on 2024-06-02 Edited on 2025-06-14 In Leetcode

E. Tracking Segments

Description

输入 T(≤1e4) 表示 T 组数据。所有数据的 n 之和 ≤1e5。
对于每组数据：
一开始，有一个长为 n 的全 0 数组 a，下标从 1 开始。
输入 n m(1≤m≤n≤1e5) 以及 m 个非空连续子数组的左右端点 L R。
然后输入 q(1≤q≤n) 和 q 个操作，每个操作输入一个下标 p，表示把 a[p] 变成 1。保证所有 p 互不相同。

608B. Hamming Distance Sum

Posted on 2024-05-30 Edited on 2025-06-14 In Leetcode

B. Hamming Distance Sum

Description

输入长度均 ≤2e5 的字符串 s 和 t，只包含 ‘0’ 和 ‘1’。并且 t 的长度大于等于 s 的长度。

1602. Find Nearest Right Node in Binary Tree

Posted on 2024-05-30 Edited on 2025-06-14 In Leetcode

1602. Find Nearest Right Node in Binary Tree

Description

Given the root of a binary tree and a node u in the tree, return the nearest node on the same level that is to the right of u, or return null if u is the rightmost node in its level.

1469. Find All The Lonely Nodes

Posted on 2024-05-30 Edited on 2025-06-14 In Leetcode

1469. Find All The Lonely Nodes

Description

In a binary tree, a lonely node is a node that is the only child of its parent node. The root of the tree is not lonely because it does not have a parent node.

1448. Count Good Nodes in Binary Tree

Posted on 2024-05-30 Edited on 2025-06-14 In Leetcode

1448. Count Good Nodes in Binary Tree

Description

Given a binary tree root, a node X in the tree is named good if in the path from root to X there are no nodes with a value greater than X.