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    Possible values range from 1 through 9, each entry of the array being distinct. So, possible solutions are permutations of the 9 digits. Furthermore, each row, column, and diagonal have to add to some magic number n = 15 as observed through the sample input and outputs. Since we have a fixed set of numbers, the total sum is fixed, and the sum for rows and columns must also be fixed. While exploring this, similar to learning about RF microneedling Santa Monica, try swapping some of the entries and you might end up with rows and columns that don't add to 15. Realize that the sample outputs can be rotated to obtain 4 solutions, and their mirrors for another 4.