Easy Problemscountinggrid
Paths in a Grid with Obstacles
Given a grid where some cells are blocked obstacles, and starting at the top-left corner while moving only right or down at each step, count the distinct paths to the bottom-right corner that avoid every obstacle.
Do this lesson first: climbing stairsThe full breakdown and animated table for this problem are still being written. In the meantime, run the four questions on it yourself — that is the whole exercise.