saddle_points.rb

class Matrix
  attr_reader :rows, :columns
  
  def initialize(str)
    @rows = str.split("\n").map { |row| row.split(" ").map(&:to_i) }
    @columns = @rows.transpose
  end 

  def saddle_points
    arr = []
        
    # iterate through each row with it's index
    # i is the row number
    @rows.each_with_index do |row, i|

      # find the maximum value in the row
      row_max = row.max

      # iterate through each value in the row
      # k cooresponds to the appropriate column index
      row.each_with_index do |row_value, k|

        # find the minumum value in the column
        column_min = @columns[k].min

        # add the row and column index to the array
        # if the value matches the min and the max
        arr << [i,k] if row_value == column_min && row_value == row_max  
      end 
    end 

    arr 
  end 
end