Given a positive integer n, find the pivot integer x such that:
- The sum of all elements between 1 and x inclusively equals the sum of all elements between x and n inclusively.
Return the pivot integer x. If no such integer exists, return -1. It is guaranteed that there will be at most one pivot index for the given input.
2486. Append Characters to String to Make Subsequence
You are given two strings s and t consisting of only lowercase English letters.
Return the minimum number of characters that need to be appended to the end of s so that t becomes a subsequence of s.
A subsequence is a string that can be derived from another string by deleting some or no characters without changing the order of the remaining characters.
2487. Remove Nodes From Linked List
You are given the head of a linked list.
Remove every node which has a node with a strictly greater value anywhere to the right side of it.
Return the head of the modified linked list.
2488. Count Subarrays With Median K
You are given an array nums of size n consisting of distinct integers from 1 to n and a positive integer k.
Return the number of non-empty subarrays in nums that have a median equal to k.
Note:
The median of an array is the middle element after sorting the array in ascending order. If the array is of even length, the median is the left middle element.
- For example, the median of [2,3,1,4] is 2, and the median of [8,4,3,5,1] is 4.
A subarray is a contiguous part of an array.