A robot starts at the top-left corner of an m x n grid and can only move right or down. Determine the total number of unique paths it can take to reach the bottom-right corner.
An ugly number is a positive integer that is divisible by at least one of the integers a, b, or c. Your task is to return the nth ugly number in the sequence formed by the integers divisible by a, b, or c.
You are given n points on a 1-D plane, where each point i is at x = i. Your task is to find the number of ways to draw exactly k non-overlapping line segments that cover two or more points, such that the endpoints are integral. Return the result modulo 10^9 + 7.
You are given an array of integers nums. The XOR total of an array is defined as the bitwise XOR of all its elements, or 0 if the array is empty. For every subset of nums, calculate the XOR total and return the sum of all XOR totals.
You are given a string word consisting of lowercase English letters. Your task is to return the total sum of the number of vowels (‘a’, ’e’, ‘i’, ‘o’, and ‘u’) present in every possible substring of word. A substring is any contiguous sequence of characters in the word.
You are given a 0-indexed integer array nums, where each element is a digit between 0 and 9. The triangular sum of nums is computed by repeatedly reducing the array by replacing each element with the sum of two consecutive elements, modulo 10. This process continues until only one element remains, which is the triangular sum. Your task is to return the triangular sum of the array.
