A robot starts at the top-left corner of an m x n grid and needs to reach the bottom-right corner. The grid contains obstacles (marked as 1) and empty cells (marked as 0). The robot can only move down or right and cannot pass through cells with obstacles. Determine the number of unique paths to the destination.
Given an m x n grid filled with non-negative integers, find a path from the top-left to the bottom-right corner that minimizes the sum of all numbers along the way. The robot can only move either right or down at each step.
You are given a large integer represented as an array of digits. Each digits[i] represents the ith digit of the integer, arranged from most significant to least significant. The task is to increment the integer by one and return the resulting digits as an array.
You are given an m x n matrix of integers. Whenever an element in the matrix is 0, you need to set all elements in the corresponding row and column to 0, but the operation must be done in place. This means you cannot use extra space for another matrix.
You are given an m x n matrix where each row is sorted in non-decreasing order, and the first integer of each row is greater than the last integer of the previous row. Given a target integer, return true if the target exists in the matrix or false otherwise. The solution must have a time complexity of O(log(m * n)).
You are given an array of integers where each element represents a color: 0 for red, 1 for white, and 2 for blue. Your task is to sort the array such that all reds (0) appear first, followed by whites (1), and finally blues (2). Solve the problem in one pass with constant extra space, without using any built-in sort functions.
