2435. Paths in Matrix Whose Sum Is Divisible by K
You are given a 0-indexed m x n integer matrix grid and an integer k. You are currently at position (0, 0) and you want to reach position (m - 1, n - 1) moving only down or right.
Return the number of paths where the sum of the elements on the path is divisible by k. Since the answer may be very large, return it modulo 109 + 7.
2434. Using a Robot to Print the Lexicographically Smallest String
You are given a string s and a robot that currently holds an empty string t. Apply one of the following operations until s and t are both empty:
- Remove the first character of a string s and give it to the robot. The robot will append this character to the string t.
- Remove the last character of a string t and give it to the robot. The robot will write this character on paper.
Return the lexicographically smallest string that can be written on the paper.
2433. Find The Original Array of Prefix Xor
You are given an integer array pref of size n. Find and return the array arr of size n that satisfies:
- pref[i] = arr[0] ^ arr[1] ^ … ^ arr[i].
Note that ^ denotes the bitwise-xor operation.
It can be proven that the answer is unique.
2432. The Employee That Worked on the Longest Task
There are n employees, each with a unique id from 0 to n - 1.
You are given a 2D integer array logs where logs[i] = [idi, leaveTimei] where:
- idi is the id of the employee that worked on the ith task, and
- leaveTimei is the time at which the employee finished the ith task. All the values leaveTimei are unique.
Note that the ith task starts the moment right after the (i - 1)th task ends, and the 0th task starts at time 0.
Return the id of the employee that worked the task with the longest time. If there is a tie between two or more employees, return the smallest id among them.