One Repaint to a Solid Block

Easy

A floor is laid out as a 3×3 grid of tiles: tiles[i][j] is 'B' for a black tile or 'W' for a white one. You may repaint **at most one** tile. Return True if the floor can then contain a 2×2 block of tiles that are all the same colour, and False otherwise.

Example 1

tiles=[['W', 'B', 'W'], ['B', 'B', 'W'], ['W', 'W', 'B']] → True

Repainting the top-left tile to B makes the top-left 2×2 block entirely black.

Example 2

tiles=[['W', 'B', 'W'], ['B', 'W', 'B'], ['W', 'B', 'W']] → False

Every 2×2 block has two tiles of each colour, so one repaint is never enough.

Example 3

tiles=[['B', 'W', 'W'], ['B', 'W', 'W'], ['B', 'B', 'B']] → True

The top-right block is already all white, so no repaint is needed.

Constraints

len(tiles) == 3
len(tiles[i]) == 3
tiles[i][j] is 'B' or 'W'

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Topics

Array Enumeration Matrix

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Input

tiles=[['W', 'B', 'W'], ['B', 'B', 'W'], ['W', 'W', 'B']]

Expected

True

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