Grid Pathfinding With Obstacles | Dataford Interview Questions

Given a 2D matrix representing a grid with potential obstructions, find the minimum number of steps required to navigate from the top-left corner to the bottom-right corner.

Use 0 for an open cell and 1 for an obstruction. Movement is allowed to any of the eight neighboring cells, including diagonals. Return -1 when the destination cannot be reached.

Input: grid, a non-empty rectangular list of lists. Output: an integer step count. For example, [[0,1,0],[0,0,1],[1,0,0]] returns 2, while a blocked start returns -1.

Constraints

1 <= len(grid) <= 1000
1 <= len(grid[0]) <= 1000
Every row has the same number of cells
Each cell is either 0 or 1
Movement is allowed in all eight directions
The step count is the number of cell-to-cell moves

Function Signature

def minimum_steps(grid):

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