(Codejam 2013) One Statement Lawnmower in Ruby

lawn_code.rb

require 'matrix' and gets.to_i.times { |i| puts "Case ##{i+1}: #{(m = Matrix[*Array.new(gets.split.map(&:to_i)[0]) { gets.split.map(&:to_i) }]).enum_for(:each_with_index).all? { |c,i,j| [m.row(i).max, m.column(j).max].min == c } ? 'YES' : 'NO'}" }

lawn_explanation.rb

require 'matrix' and                            # require the matrix library
gets.to_i                                       # read the number of testcases
  .times { |i|                                  # for each test case
    puts "Case ##{i+1}: #{                      # print the case number
      (m = Matrix[*                             # create a matrix from arrays
        Array.new(gets.split.map(&:to_i)[0]) {  # read 2 numbers N,M. create array of size N
          gets.split.map(&:to_i)                # each row, read in numbers for each row
        }
      ]).enum_for(:each_with_index)             # check every cell
        .all? { |c,i,j|
          [
            m.row(i).max,                       # look horizontally and take the max height
            m.column(j).max                     # look vertically and take the max height
          ].min == c                            # the minimum of the two must equal to current height
        } ? 'YES' : 'NO'                        # format the text
    }"
  }