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Python grid and matrix problems

Walk, fill and search rows and columns of 2D data in Python, on problems with tests.

Start with Sum of Both Diagonals

Beginner

  1. 229. Sum of Both DiagonalsCorner to corner, both ways across the square30 XP6 min
  2. 250. Island CoastlineHow long is the coastline of this little island?40 XP10 min

Intermediate

  1. 273. Minesweeper NumbersCount the mines hiding around every square of the board60 XP12 min
  2. 278. Zero Out Rows and ColumnsOne failed sensor spoils its whole row and column60 XP10 min
  3. 284. Paint Bucket FillThe paint bucket tool of a drawing program, from the inside65 XP14 min
  4. 288. Saddle PointsSpots on a map shaped like the middle of a saddle65 XP12 min
  5. 309. Search a Sorted GridRows in order, columns in order: where is the number hiding?70 XP12 min

Advanced

  1. 351. Largest Square Solar PanelThe biggest square solar panel that fits on a patchy roof120 XP25 min
  2. 354. Robot Across the WarehouseThe quickest way across a warehouse floor, diagonals allowed120 XP25 min
  3. 376. Largest Plus-Shaped Flower BedLay out the biggest plus-shaped flower bed on a rocky plot135 XP28 min

Expert

  1. 445. Knight on an Endless BoardA chess knight on a board that never ends: how quickly can it get there?220 XP45 min
  2. 449. Sledgehammer MazeA sledgehammer with a few swings left: how fast can you cross the maze?220 XP40 min
  3. 485. Count the Rugs That FitA floor with cracked tiles: how many rectangular rugs fit on the good ones?260 XP55 min
  4. 493. Rain on a Height MapRain pools in the hollows of a blocky landscape: how much stays?270 XP55 min

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