Solution:Minimum Time Takes to Reach Destination Without Drowning

Explore how to determine the minimum time it takes to reach a destination on a grid with obstacles and spreading floods. Learn to apply a breadth-first search approach to simulate flood expansion and player movement, and understand the method to handle dynamic constraints to find the shortest safe path or determine if none exists.

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Statement
Solution
Time complexity
Space complexity

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:

You can’t step on stone cells.
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 in seconds, or $-1$ if no path exists between them.

Note: The destination will never be flooded.

Constraints:

$2 \leq$ ...