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Solution:Minimum Time Takes to Reach Destination Without Drowning

Understand how to apply a breadth-first search approach for matrix traversal to determine the minimum time required to safely reach a destination cell from a source cell in a grid affected by expanding floods and obstacles. This lesson helps you navigate constraints like flooded and stone cells, alternating flood spread and player movement to find the optimal path or conclude no path exists.

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Statement

Given a m x n grid of the string land. It consists of the following types of cells:

  • S: Source cell where you are standing initially.

  • D: Destination cell where you have to reach.

  • .: These cells are empty.

  • X: These cells are stone.

  • *: These cells are flooded.

Each second, you can move to a neighboring cell directly next to your current one. At the same time, any empty cell next to a flooded cell also becomes flooded. There are two challenges in your path:

  1. You can’t step on stone cells.

  2. You can’t step on flooded cells or cells that will flood right when you try to step on them because you’ll drown.

Return the minimum time it takes you to reach the destination from the source ...