Please don't use tangent and sine functions
Not a general solution. Passes only due to small number of cases in the Test Suite.
Which values occur exactly three times?
3306 Solvers
Replace NaNs with the number that appears to its left in the row.
1710 Solvers
Back to basics 8 - Matrix Diagonals
707 Solvers
200 Solvers
212 Solvers