オフラインリアルタイムどう書く #7 の問題を解いた http://nabetani.sakura.ne.jp/hena/ord7xysort/

xy_sort.rb

def sort_with_other_row(table, idx)
  row = table[idx]

  # [ソート前のカラムのインデックス値, ...]
  ex_sort_idxs = row.map
    .with_index { |e, idx| [e, idx] }
    .sort_by
    .with_index { |cell, idx| [cell.first, idx] }
    .map(&:last)

  next_table = Array.new(6).map { Array.new }

  # 全て行のカラムを ex_sort_idxs の並び順に従って、並び替える
  ex_sort_idxs.each do |column_idx|
    table.each_with_index { |row, row_idx| next_table[row_idx] << row[column_idx] }
  end

  next_table
end

def solve(str)
  table = [
    [4,1,4,2,1,3],
    [7,3,2,0,5,0],
    [2,3,6,0,6,7],
    [6,4,5,7,5,1],
    [3,1,6,6,2,4],
    [6,0,5,5,5,1]
  ]

  str.chars.each do |char|
    if char =~ %r{[A-F]}
      idx = char.ord - "A".ord

      table = sort_with_other_row(table, idx)
    end

    if char =~ %r{[u-z]}
      table = table.transpose
      idx = char.ord - "u".ord

      table = sort_with_other_row(table, idx).transpose
    end
  end

  table.first.join
end

require 'rspec'

describe "#solve" do
  it { expect(solve("AvEx")).to eq "305027" }
  it { expect(solve("A")).to eq "112344" }
  it { expect(solve("C")).to eq "241413" }
  it { expect(solve("F")).to eq "134214" }
  it { expect(solve("u")).to eq "236067" }
  it { expect(solve("w")).to eq "732050" }
  it { expect(solve("y")).to eq "414213" }
  it { expect(solve("yx")).to eq "732050" }
  it { expect(solve("ux")).to eq "236067" }
  it { expect(solve("FAuFBvFCw")).to eq "300527" }
end