backtracking

def backtrack(grid, row)
  if matches?(grid, row)
    if row == (grid.length - 1)  # If we've matched everything!
      return true
    end
  else
    return false
  end

  for i = 0; i < grid.length, i++
    rotate(grid, row + 1)
    if backtrack(grid, row + 1)
      return true
    end
  end
end