#840
Magic Squares In Grid
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Description
A 3 x 3 magic square is a 3 x 3 grid whose cells contain the distinct integers from 1 to 9 and whose rows, columns, and both main diagonals all share the same sum.
Given a row x col integer grid, count how many 3 x 3 contiguous subgrids form a magic square.
Note: even though a magic square only uses 1-9, values in grid may be as large as 15.
Example 1:
Input: grid = [[4,3,8,4],[9,5,1,9],[2,7,6,2]]
Output: 1
Explanation:
The following subgrid is a 3 x 3 magic square:
Example 2:
while this one is not:
Example 3:
In total, there is only one magic square inside the given grid.
Example 4:
Input: grid = [[8]]
Output: 0
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