Medium data structure and algorithm practice puzzle.
A hero crosses a trapped room from the top-left tile to the bottom-right, moving only right or down. Each tile deals the damage written on it, including the first and last. Return the least total damage possible. With dynamic programming, the cheapest way to reach a tile is its own damage plus the cheaper of the tile above and the tile to the left, so fill the grid row by row and the bottom-right answer builds itself.
Solve it three ways: snap the jigsaw pieces together, fill in the blanks, or type it from scratch against the tests. This one is free.
Every line of the solution comes with a note explaining why it is there, and a step by step replay shows the code running. At level 3, where you type it yourself, you can ask for an AI mock interview on this problem that ends with a hiring manager's scorecard.
Then grow it into a real project with the Software Engineer button: this puzzle becomes the Entity Capacity Planner, a pipeline you can run and download. See every Software Engineer project.
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