2385. Amount of Time for Binary Tree to Be Infected
You are given the root of a binary tree with unique values, and an integer start. At minute 0, an infection starts from the node with value start.
Each minute, a node becomes infected if:
- The node is currently uninfected.
- The node is adjacent to an infected node.
Return the number of minutes needed for the entire tree to be infected.
2386. Find the K-Sum of an Array
You are given an integer array nums and a positive integer k. You can choose any subsequence of the array and sum all of its elements together.
We define the K-Sum of the array as the kth largest subsequence sum that can be obtained (not necessarily distinct).
Return the K-Sum of the array.
A subsequence is an array that can be derived from another array by deleting some or no elements without changing the order of the remaining elements.
Note that the empty subsequence is considered to have a sum of 0.
2382. Maximum Segment Sum After Removals
You are given two 0-indexed integer arrays nums and removeQueries, both of length n. For the ith query, the element in nums at the index removeQueries[i] is removed, splitting nums into different segments.
A segment is a contiguous sequence of positive integers in nums. A segment sum is the sum of every element in a segment.
Return an integer array answer, of length n, where answer[i] is the maximum segment sum after applying the ith removal.
Note: The same index will not be removed more than once.
You are given a string s of lowercase English letters and a 2D integer array shifts where shifts[i] = [starti, endi, directioni]. For every i, shift the characters in s from the index starti to the index endi (inclusive) forward if directioni = 1, or shift the characters backward if directioni = 0.
Shifting a character forward means replacing it with the next letter in the alphabet (wrapping around so that ‘z’ becomes ‘a’). Similarly, shifting a character backward means replacing it with the previous letter in the alphabet (wrapping around so that ‘a’ becomes ‘z’).
Return the final string after all such shifts to s are applied.
2380. Time Needed to Rearrange a Binary String
You are given a binary string s. In one second, all occurrences of “01” are simultaneously replaced with “10”. This process repeats until no occurrences of “01” exist.
Return the number of seconds needed to complete this process.
2379. Minimum Recolors to Get K Consecutive Black Blocks
You are given a 0-indexed string blocks of length n, where blocks[i] is either ‘W’ or ‘B’, representing the color of the ith block. The characters ‘W’ and ‘B’ denote the colors white and black, respectively.
You are also given an integer k, which is the desired number of consecutive black blocks.
In one operation, you can recolor a white block such that it becomes a black block.
Return the minimum number of operations needed such that there is at least one occurrence of k consecutive black blocks.