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.

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2484. Count Palindromic Subsequences

Given a string of digits s, return the number of palindromic subsequences of s having length 5. Since the answer may be very large, return it modulo 109 + 7.

Note:

• A string is palindromic if it reads the same forward and backward.
• 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.

2483. Minimum Penalty for a Shop

You are given the customer visit log of a shop represented by a 0-indexed string customers consisting only of characters ‘N’ and ‘Y’:

• if the ith character is ‘Y’, it means that customers come at the ith hour
• whereas ‘N’ indicates that no customers come at the ith hour.

If the shop closes at the jth hour (0 <= j <= n), the penalty is calculated as follows:

• For every hour when the shop is open and no customers come, the penalty increases by 1.
• For every hour when the shop is closed and customers come, the penalty increases by 1.

Return the earliest hour at which the shop must be closed to incur a minimum penalty.

Note that if a shop closes at the jth hour, it means the shop is closed at the hour j.

2482. Difference Between Ones and Zeros in Row and Column

You are given a 0-indexed m x n binary matrix grid.

A 0-indexed m x n difference matrix diff is created with the following procedure:

• Let the number of ones in the ith row be onesRowi.
• Let the number of ones in the jth column be onesColj.
• Let the number of zeros in the ith row be zerosRowi.
• Let the number of zeros in the jth column be zerosColj.
• diff[i][j] = onesRowi + onesColj - zerosRowi - zerosColj

Return the difference matrix diff.

2481. Minimum Cuts to Divide a Circle

A valid cut in a circle can be:

• A cut that is represented by a straight line that touches two points on the edge of the circle and passes through its center, or
• A cut that is represented by a straight line that touches one point on the edge of the circle and its center.

Some valid and invalid cuts are shown in the figures below.

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Maximum Unique Segment

Prefix Zeros

Chef and Hamming Distance of arrays