From d37d2ba60310084f9e4b8d9e85c9ccd3d6f245f1 Mon Sep 17 00:00:00 2001
From: Marc Heiligers <marc@eternal.co.za>
Date: Sun, 28 Feb 2021 16:47:50 -0700
Subject: [PATCH 1/4] BasicArrayTwoD, top row drawn, and trying to logic my way
 through the next row

---
 02 Amazing/ruby/amazing.rb | 276 +++++++++++++++++++++++++++++++++++++
 1 file changed, 276 insertions(+)
 create mode 100644 02 Amazing/ruby/amazing.rb

diff --git a/02 Amazing/ruby/amazing.rb b/02 Amazing/ruby/amazing.rb
new file mode 100644
index 00000000..7e7db0ce
--- /dev/null
+++ b/02 Amazing/ruby/amazing.rb	
@@ -0,0 +1,276 @@
+# frozen_string_literal: true
+
+# BASIC arrays are 1-based, unlike Ruby 0-based arrays
+class BasicArrayTwoD
+  def initialize(width, height)
+    @val = Array.new(height) { Array.new(width, 0) }
+  end
+
+  def [](x, y)
+    @val[y - 1][x - 1]
+  end
+
+  def []=(x, y, n)
+    @val[y - 1][x - 1] = n
+  end
+
+  def to_s
+    @val.map { |r| r.join(' ') }.join("\n")
+  end
+end
+
+# 10 PRINT TAB(28);"AMAZING PROGRAM"
+# 20 PRINT TAB(15);"CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY"
+# 30 PRINT:PRINT:PRINT:PRINT
+puts ' ' * 28 + 'AMAZING PROGRAM'
+puts ' ' * 15 + 'CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY'
+puts "\n" * 4
+
+# 100 INPUT "WHAT ARE YOUR WIDTH AND LENGTH";H,V
+# 102 IF H<>1 AND V<>1 THEN 110
+# 104 PRINT "MEANINGLESS DIMENSIONS.  TRY AGAIN.":GOTO 100
+def ask_dimensions
+  print 'WHAT ARE YOUR WIDTH AND LENGTH? '
+  h = gets.to_i
+  print '?? '
+  v = gets.to_i
+  [h, v]
+end
+
+h, v = ask_dimensions
+while h < 1 || v < 1
+  puts "MEANINGLESS DIMENSIONS.  TRY AGAIN."
+  h, v = ask_dimensions
+end
+
+# 110 DIM W(H,V),V(H,V)
+# BASIC programs can have the same variable names for different types,
+#   so the v array is not the same as the v int. Here we're using suffixes.
+w_arr = BasicArrayTwoD.new(h, v)
+v_arr = BasicArrayTwoD.new(h, v)
+
+# 120 PRINT
+# 130 PRINT
+# 140 PRINT
+# 150 PRINT
+puts "\n" * 4
+
+# 160 Q=0:Z=0:X=INT(RND(1)*H+1)
+q = 0
+z = 0
+
+def draw_top(x, h)
+  # 165 FOR I=1 TO H
+  # 170 IF I=X THEN 173
+  # 171 PRINT ".--";:GOTO 180
+  # 173 PRINT ".  ";
+  # 180 NEXT I
+  (1..h).each do |i|
+    if i == x
+      print i == 1 ? '┏  ' : '┳  '
+    else
+      print i == 1 ? '┏━━' : '┳━━'
+    end
+  end
+
+  # 190 PRINT "."
+  puts '┓'
+
+  x # return this because we need it
+end
+
+# x represents the location of the opening
+x = (rand * h).round + 1
+draw_top(x, h)
+
+# 195 C=1:W(X,1)=C:C=C+1
+c = 1
+w_arr[x, 1] = c # This marks the opening in the first row
+c += 1
+
+puts w_arr
+
+# 200 R=X:S=1:GOTO 260
+r = x
+s = 1
+# 260 IF R-1=0 THEN 530
+if r - 1 == 0
+  # 530 IF S-1=0 THEN 670
+  if s - 1 == 0
+    # 670 IF R=H THEN 740
+    if r == h
+      # 740 IF S<>V THEN 760
+      if s != v
+        # 760 IF W(R,S+1)<>0 THEN 780
+        if w_arr[r, s + 1] != 0
+          # 780 GOTO 1000
+          # Well, we'll just go directly to 1000
+          # 1000 GOTO 210
+          # Well, now. I just got here, now back to 210
+          # 210 IF R<>H THEN 240
+          if r != h
+            # 240 R=R+1
+            r += 1
+            # 250 IF W(R,S)=0 THEN 210
+            if w_arr[r, s] == 0
+              # GOTO 210 -- this is a loop
+            end
+            # 260 IF R-1=0 THEN 530
+            if r - 1 == 0
+              # 530 IF S-1=0 THEN 670
+              # 540 IF W(R,S-1)<>0 THEN 670
+              if s - 1 == 0 || w_arr[r, s - 1] != 0
+                # 670 IF R=H THEN 740
+                # 680 IF W(R+1,S)<>0 THEN 740
+                # 685 IF S<>V THEN 700
+                # 690 IF Z=1 THEN 730
+                # 695 Q=1:GOTO 710
+              end
+              # 545 IF R=H THEN 610
+              # 547 IF W(R+1,S)<>0 THEN 610
+              if r == h || w_arr[r + 1, s] != 0
+                # 610 IF S<>V THEN 630
+                # 620 IF Z=1 THEN 660
+                # 625 Q=1:GOTO 640
+              end
+              # 550 IF S<>V THEN 560
+              if s != v
+                # 560 IF W(R,S+1)<>0 THEN 590
+                # 570 X=INT(RND(1)*3+1)
+                # 580 ON X GOTO 820,860,910
+              end
+              # 552 IF Z=1 THEN 590
+              if z == 1
+                # 590 X=INT(RND(1)*2+1)
+                # 600 ON X GOTO 820,860
+              end
+              # 554 Q=1:GOTO 570
+              q = 1
+              # 570 X=INT(RND(1)*3+1)
+              # 580 ON X GOTO 820,860,910
+            end
+          end
+        end
+      end
+    end
+  end
+end
+
+# 210 IF R<>H THEN 240
+# 215 IF S<>V THEN 230
+# 220 R=1:S=1:GOTO 250
+# 230 R=1:S=S+1:GOTO 250
+# 240 R=R+1
+# 250 IF W(R,S)=0 THEN 210
+# 260 IF R-1=0 THEN 530
+# 265 IF W(R-1,S)<>0 THEN 530
+# 270 IF S-1=0 THEN 390
+# 280 IF W(R,S-1)<>0 THEN 390
+# 290 IF R=H THEN 330
+# 300 IF W(R+1,S)<>0 THEN 330
+# 310 X=INT(RND(1)*3+1)
+# 320 ON X GOTO 790,820,860
+# 330 IF S<>V THEN 340
+# 334 IF Z=1 THEN 370
+# 338 Q=1:GOTO 350
+# 340 IF W(R,S+1)<>0 THEN 370
+# 350 X=INT(RND(1)*3+1)
+# 360 ON X GOTO 790,820,910
+# 370 X=INT(RND(1)*2+1)
+# 380 ON X GOTO 790,820
+# 390 IF R=H THEN 470
+# 400 IF W(R+1,S)<>0 THEN 470
+# 405 IF S<>V THEN 420
+# 410 IF Z=1 THEN 450
+# 415 Q=1:GOTO 430
+# 420 IF W(R,S+1)<>0 THEN 450
+# 430 X=INT(RND(1)*3+1)
+# 440 ON X GOTO 790,860,910
+# 450 X=INT(RND(1)*2+1)
+# 460 ON X GOTO 790,860
+# 470 IF S<>V THEN 490
+# 480 IF Z=1 THEN 520
+# 485 Q=1:GOTO 500
+# 490 IF W(R,S+1)<>0 THEN 520
+# 500 X=INT(RND(1)*2+1)
+# 510 ON X GOTO 790,910
+# 520 GOTO 790
+# 530 IF S-1=0 THEN 670
+# 540 IF W(R,S-1)<>0 THEN 670
+# 545 IF R=H THEN 610
+# 547 IF W(R+1,S)<>0 THEN 610
+# 550 IF S<>V THEN 560
+# 552 IF Z=1 THEN 590
+# 554 Q=1:GOTO 570
+# 560 IF W(R,S+1)<>0 THEN 590
+# 570 X=INT(RND(1)*3+1)
+# 580 ON X GOTO 820,860,910
+# 590 X=INT(RND(1)*2+1)
+# 600 ON X GOTO 820,860
+# 610 IF S<>V THEN 630
+# 620 IF Z=1 THEN 660
+# 625 Q=1:GOTO 640
+# 630 IF W(R,S+1)<>0 THEN 660
+# 640 X=INT(RND(1)*2+1)
+# 650 ON X GOTO 820,910
+# 660 GOTO 820
+# 670 IF R=H THEN 740
+# 680 IF W(R+1,S)<>0 THEN 740
+# 685 IF S<>V THEN 700
+# 690 IF Z=1 THEN 730
+# 695 Q=1:GOTO 710
+# 700 IF W(R,S+1)<>0 THEN 730
+# 710 X=INT(RND(1)*2+1)
+# 720 ON X GOTO 860,910
+# 730 GOTO 860
+# 740 IF S<>V THEN 760
+# 750 IF Z=1 THEN 780
+# 755 Q=1:GOTO 770
+# 760 IF W(R,S+1)<>0 THEN 780
+# 770 GOTO 910
+# 780 GOTO 1000
+# 790 W(R-1,S)=C
+# 800 C=C+1:V(R-1,S)=2:R=R-1
+# 810 IF C=H*V+1 THEN 1010
+# 815 Q=0:GOTO 260
+# 820 W(R,S-1)=C
+# 830 C=C+1
+# 840 V(R,S-1)=1:S=S-1:IF C=H*V+1 THEN 1010
+# 850 Q=0:GOTO 260
+# 860 W(R+1,S)=C
+# 870 C=C+1:IF V(R,S)=0 THEN 880
+# 875 V(R,S)=3:GOTO 890
+# 880 V(R,S)=2
+# 890 R=R+1
+# 900 IF C=H*V+1 THEN 1010
+# 905 GOTO 530
+# 910 IF Q=1 THEN 960
+# 920 W(R,S+1)=C:C=C+1:IF V(R,S)=0 THEN 940
+# 930 V(R,S)=3:GOTO 950
+# 940 V(R,S)=1
+# 950 S=S+1:IF C=H*V+1 THEN 1010
+# 955 GOTO 260
+# 960 Z=1
+# 970 IF V(R,S)=0 THEN 980
+# 975 V(R,S)=3:Q=0:GOTO 1000
+# 980 V(R,S)=1:Q=0:R=1:S=1:GOTO 250
+# 1000 GOTO 210
+# 1010 FOR J=1 TO V
+# 1011 PRINT "I";
+# 1012 FOR I=1 TO H
+# 1013 IF V(I,J)<2 THEN 1030
+# 1020 PRINT "   ";
+# 1021 GOTO 1040
+# 1030 PRINT "  I";
+# 1040 NEXT I
+# 1041 PRINT
+# 1043 FOR I=1 TO H
+# 1045 IF V(I,J)=0 THEN 1060
+# 1050 IF V(I,J)=2 THEN 1060
+# 1051 PRINT ":  ";
+# 1052 GOTO 1070
+# 1060 PRINT ":--";
+# 1070 NEXT I
+# 1071 PRINT "."
+# 1072 NEXT J
+# 1073 END

From c4b2260ae7c5faa3f20161eb84ade951a5a78b18 Mon Sep 17 00:00:00 2001
From: Marc Heiligers <marc@eternal.co.za>
Date: Sat, 6 Mar 2021 11:42:35 -0700
Subject: [PATCH 2/4] Translate Python version for main algorithm

---
 02 Amazing/ruby/amazing.rb | 374 +++++++++++++------------------------
 1 file changed, 130 insertions(+), 244 deletions(-)

diff --git a/02 Amazing/ruby/amazing.rb b/02 Amazing/ruby/amazing.rb
index 7e7db0ce..c14148b1 100644
--- a/02 Amazing/ruby/amazing.rb	
+++ b/02 Amazing/ruby/amazing.rb	
@@ -1,276 +1,162 @@
 # frozen_string_literal: true
 
-# BASIC arrays are 1-based, unlike Ruby 0-based arrays
+# Set up a constant hash for directions
+DIRECTIONS = {
+  left: 0,
+  up: 1,
+  right: 2,
+  down: 3
+}.freeze
+
+EXIT_DOWN = 1
+EXIT_RIGHT = 2
+
+# BASIC arrays are 1-based, unlike Ruby 0-based arrays,
+#   and this class simulates that. BASIC arrays are also zero-filled,
+#   which is also done here.
 class BasicArrayTwoD
-  def initialize(width, height)
-    @val = Array.new(height) { Array.new(width, 0) }
+  def initialize(rows, cols)
+    @val = Array.new(rows) { Array.new(cols, 0) }
   end
 
-  def [](x, y)
-    @val[y - 1][x - 1]
+  def [](row, col = nil)
+    if col
+      @val[row - 1][col - 1]
+    else
+      @val[row - 1]
+    end
   end
 
-  def []=(x, y, n)
-    @val[y - 1][x - 1] = n
+  def []=(row, col, n)
+    @val[row - 1][col - 1] = n
   end
 
   def to_s
-    @val.map { |r| r.join(' ') }.join("\n")
+    @val.map { |row| row.join(' ') }.join("\n")
   end
 end
 
-# 10 PRINT TAB(28);"AMAZING PROGRAM"
-# 20 PRINT TAB(15);"CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY"
-# 30 PRINT:PRINT:PRINT:PRINT
-puts ' ' * 28 + 'AMAZING PROGRAM'
-puts ' ' * 15 + 'CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY'
-puts "\n" * 4
-
-# 100 INPUT "WHAT ARE YOUR WIDTH AND LENGTH";H,V
-# 102 IF H<>1 AND V<>1 THEN 110
-# 104 PRINT "MEANINGLESS DIMENSIONS.  TRY AGAIN.":GOTO 100
-def ask_dimensions
-  print 'WHAT ARE YOUR WIDTH AND LENGTH? '
-  h = gets.to_i
-  print '?? '
-  v = gets.to_i
-  [h, v]
-end
-
-h, v = ask_dimensions
-while h < 1 || v < 1
-  puts "MEANINGLESS DIMENSIONS.  TRY AGAIN."
-  h, v = ask_dimensions
-end
-
-# 110 DIM W(H,V),V(H,V)
-# BASIC programs can have the same variable names for different types,
-#   so the v array is not the same as the v int. Here we're using suffixes.
-w_arr = BasicArrayTwoD.new(h, v)
-v_arr = BasicArrayTwoD.new(h, v)
-
-# 120 PRINT
-# 130 PRINT
-# 140 PRINT
-# 150 PRINT
-puts "\n" * 4
-
-# 160 Q=0:Z=0:X=INT(RND(1)*H+1)
-q = 0
-z = 0
-
-def draw_top(x, h)
-  # 165 FOR I=1 TO H
-  # 170 IF I=X THEN 173
-  # 171 PRINT ".--";:GOTO 180
-  # 173 PRINT ".  ";
-  # 180 NEXT I
-  (1..h).each do |i|
-    if i == x
+def draw_top(entry, width)
+  (1..width).each do |i|
+    if i == entry
       print i == 1 ? '┏  ' : '┳  '
     else
       print i == 1 ? '┏━━' : '┳━━'
     end
   end
 
-  # 190 PRINT "."
   puts '┓'
-
-  x # return this because we need it
 end
 
-# x represents the location of the opening
-x = (rand * h).round + 1
-draw_top(x, h)
+def draw_row(row)
+  print '┃'
+  row.each { |val| print val < 2 ? '  ┃' : '   ' }
+  puts
+  row.each { |val| print val == 0 || val == 2 ? '┣━━' : '┃  ' }
+  puts '┫'
+end
 
-# 195 C=1:W(X,1)=C:C=C+1
+
+# 10 PRINT TAB(28);"AMAZING PROGRAM"
+# 20 PRINT TAB(15);"CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY"
+# 30 PRINT:PRINT:PRINT:PRINT
+puts ' ' * 28 + 'AMAZING PROGRAM'
+puts ' ' * 15 + 'CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY'
+puts "\n" * 3
+
+# 100 INPUT "WHAT ARE YOUR WIDTH AND LENGTH";H,V
+# 102 IF H<>1 AND V<>1 THEN 110
+# 104 PRINT "MEANINGLESS DIMENSIONS.  TRY AGAIN.":GOTO 100
+def ask_dimensions
+  print 'WHAT ARE YOUR WIDTH AND HEIGHT? '
+  width = gets.to_i
+  print '?? '
+  height = gets.to_i
+  [width, height]
+end
+
+width, height = ask_dimensions
+while width <= 1 || height <= 1
+  puts "MEANINGLESS DIMENSIONS.  TRY AGAIN."
+  width, height = ask_dimensions
+end
+
+# 110 DIM W(H,V),V(H,V)
+# BASIC programs can have the same variable names for different types,
+#   so the v array is not the same as the v int. Here we're renaming the arrays
+#   to have more friendly names
+used = BasicArrayTwoD.new(height, width)
+walls = BasicArrayTwoD.new(height, width)
+
+puts "\n" * 3
+
+
+# entry represents the location of the opening
+entry = (rand * width).round + 1
+
+# Set up our current row and column, starting at the top and the locations of the opening
+row = 1
+col = entry
 c = 1
-w_arr[x, 1] = c # This marks the opening in the first row
+used[row, col] = c # This marks the opening in the first row
 c += 1
 
-puts w_arr
+while c != width * height + 1 do
+  # remove possible directions that are blocked or
+  # hit cells that we have already processed
+  possible_dirs = DIRECTIONS.keys
+  if col == 0 || used[row, col - 1] != 0
+    possible_dirs.delete(:left)
+  end
+  if row == 0 || used[row - 1, col] != 0
+    possible_dirs.delete(:up)
+  end
+  if col == width || used[row, col + 1] != 0
+    possible_dirs.delete(:right)
+  end
+  if row == height || used[row + 1, col] != 0
+    possible_dirs.delete(:down)
+  end
 
-# 200 R=X:S=1:GOTO 260
-r = x
-s = 1
-# 260 IF R-1=0 THEN 530
-if r - 1 == 0
-  # 530 IF S-1=0 THEN 670
-  if s - 1 == 0
-    # 670 IF R=H THEN 740
-    if r == h
-      # 740 IF S<>V THEN 760
-      if s != v
-        # 760 IF W(R,S+1)<>0 THEN 780
-        if w_arr[r, s + 1] != 0
-          # 780 GOTO 1000
-          # Well, we'll just go directly to 1000
-          # 1000 GOTO 210
-          # Well, now. I just got here, now back to 210
-          # 210 IF R<>H THEN 240
-          if r != h
-            # 240 R=R+1
-            r += 1
-            # 250 IF W(R,S)=0 THEN 210
-            if w_arr[r, s] == 0
-              # GOTO 210 -- this is a loop
-            end
-            # 260 IF R-1=0 THEN 530
-            if r - 1 == 0
-              # 530 IF S-1=0 THEN 670
-              # 540 IF W(R,S-1)<>0 THEN 670
-              if s - 1 == 0 || w_arr[r, s - 1] != 0
-                # 670 IF R=H THEN 740
-                # 680 IF W(R+1,S)<>0 THEN 740
-                # 685 IF S<>V THEN 700
-                # 690 IF Z=1 THEN 730
-                # 695 Q=1:GOTO 710
-              end
-              # 545 IF R=H THEN 610
-              # 547 IF W(R+1,S)<>0 THEN 610
-              if r == h || w_arr[r + 1, s] != 0
-                # 610 IF S<>V THEN 630
-                # 620 IF Z=1 THEN 660
-                # 625 Q=1:GOTO 640
-              end
-              # 550 IF S<>V THEN 560
-              if s != v
-                # 560 IF W(R,S+1)<>0 THEN 590
-                # 570 X=INT(RND(1)*3+1)
-                # 580 ON X GOTO 820,860,910
-              end
-              # 552 IF Z=1 THEN 590
-              if z == 1
-                # 590 X=INT(RND(1)*2+1)
-                # 600 ON X GOTO 820,860
-              end
-              # 554 Q=1:GOTO 570
-              q = 1
-              # 570 X=INT(RND(1)*3+1)
-              # 580 ON X GOTO 820,860,910
-            end
-          end
-        end
+  # If we can move in a direction, move and make opening
+  if possible_dirs.size != 0
+    direction = possible_dirs.sample # pick a random direction
+    if direction == :left
+      col = col - 1
+      walls[row, col] = EXIT_RIGHT
+    elsif direction == :up
+      row = row - 1
+      walls[row, col] = EXIT_DOWN
+    elsif direction == :right
+      walls[row, col] += EXIT_RIGHT
+      col = col + 1
+    elsif direction == :down
+      walls[row, col] += EXIT_DOWN
+      row = row + 1
+    end
+    used[row, col] = c
+    c = c + 1
+  # otherwise, move to the next used cell, and try again
+  else
+    while true do
+      if col != width
+        col += 1
+      elsif row != height
+        row += 1
+        col = 1
+      else
+        row = col = 1
       end
+      break if used[row, col] != 0
     end
   end
 end
 
-# 210 IF R<>H THEN 240
-# 215 IF S<>V THEN 230
-# 220 R=1:S=1:GOTO 250
-# 230 R=1:S=S+1:GOTO 250
-# 240 R=R+1
-# 250 IF W(R,S)=0 THEN 210
-# 260 IF R-1=0 THEN 530
-# 265 IF W(R-1,S)<>0 THEN 530
-# 270 IF S-1=0 THEN 390
-# 280 IF W(R,S-1)<>0 THEN 390
-# 290 IF R=H THEN 330
-# 300 IF W(R+1,S)<>0 THEN 330
-# 310 X=INT(RND(1)*3+1)
-# 320 ON X GOTO 790,820,860
-# 330 IF S<>V THEN 340
-# 334 IF Z=1 THEN 370
-# 338 Q=1:GOTO 350
-# 340 IF W(R,S+1)<>0 THEN 370
-# 350 X=INT(RND(1)*3+1)
-# 360 ON X GOTO 790,820,910
-# 370 X=INT(RND(1)*2+1)
-# 380 ON X GOTO 790,820
-# 390 IF R=H THEN 470
-# 400 IF W(R+1,S)<>0 THEN 470
-# 405 IF S<>V THEN 420
-# 410 IF Z=1 THEN 450
-# 415 Q=1:GOTO 430
-# 420 IF W(R,S+1)<>0 THEN 450
-# 430 X=INT(RND(1)*3+1)
-# 440 ON X GOTO 790,860,910
-# 450 X=INT(RND(1)*2+1)
-# 460 ON X GOTO 790,860
-# 470 IF S<>V THEN 490
-# 480 IF Z=1 THEN 520
-# 485 Q=1:GOTO 500
-# 490 IF W(R,S+1)<>0 THEN 520
-# 500 X=INT(RND(1)*2+1)
-# 510 ON X GOTO 790,910
-# 520 GOTO 790
-# 530 IF S-1=0 THEN 670
-# 540 IF W(R,S-1)<>0 THEN 670
-# 545 IF R=H THEN 610
-# 547 IF W(R+1,S)<>0 THEN 610
-# 550 IF S<>V THEN 560
-# 552 IF Z=1 THEN 590
-# 554 Q=1:GOTO 570
-# 560 IF W(R,S+1)<>0 THEN 590
-# 570 X=INT(RND(1)*3+1)
-# 580 ON X GOTO 820,860,910
-# 590 X=INT(RND(1)*2+1)
-# 600 ON X GOTO 820,860
-# 610 IF S<>V THEN 630
-# 620 IF Z=1 THEN 660
-# 625 Q=1:GOTO 640
-# 630 IF W(R,S+1)<>0 THEN 660
-# 640 X=INT(RND(1)*2+1)
-# 650 ON X GOTO 820,910
-# 660 GOTO 820
-# 670 IF R=H THEN 740
-# 680 IF W(R+1,S)<>0 THEN 740
-# 685 IF S<>V THEN 700
-# 690 IF Z=1 THEN 730
-# 695 Q=1:GOTO 710
-# 700 IF W(R,S+1)<>0 THEN 730
-# 710 X=INT(RND(1)*2+1)
-# 720 ON X GOTO 860,910
-# 730 GOTO 860
-# 740 IF S<>V THEN 760
-# 750 IF Z=1 THEN 780
-# 755 Q=1:GOTO 770
-# 760 IF W(R,S+1)<>0 THEN 780
-# 770 GOTO 910
-# 780 GOTO 1000
-# 790 W(R-1,S)=C
-# 800 C=C+1:V(R-1,S)=2:R=R-1
-# 810 IF C=H*V+1 THEN 1010
-# 815 Q=0:GOTO 260
-# 820 W(R,S-1)=C
-# 830 C=C+1
-# 840 V(R,S-1)=1:S=S-1:IF C=H*V+1 THEN 1010
-# 850 Q=0:GOTO 260
-# 860 W(R+1,S)=C
-# 870 C=C+1:IF V(R,S)=0 THEN 880
-# 875 V(R,S)=3:GOTO 890
-# 880 V(R,S)=2
-# 890 R=R+1
-# 900 IF C=H*V+1 THEN 1010
-# 905 GOTO 530
-# 910 IF Q=1 THEN 960
-# 920 W(R,S+1)=C:C=C+1:IF V(R,S)=0 THEN 940
-# 930 V(R,S)=3:GOTO 950
-# 940 V(R,S)=1
-# 950 S=S+1:IF C=H*V+1 THEN 1010
-# 955 GOTO 260
-# 960 Z=1
-# 970 IF V(R,S)=0 THEN 980
-# 975 V(R,S)=3:Q=0:GOTO 1000
-# 980 V(R,S)=1:Q=0:R=1:S=1:GOTO 250
-# 1000 GOTO 210
-# 1010 FOR J=1 TO V
-# 1011 PRINT "I";
-# 1012 FOR I=1 TO H
-# 1013 IF V(I,J)<2 THEN 1030
-# 1020 PRINT "   ";
-# 1021 GOTO 1040
-# 1030 PRINT "  I";
-# 1040 NEXT I
-# 1041 PRINT
-# 1043 FOR I=1 TO H
-# 1045 IF V(I,J)=0 THEN 1060
-# 1050 IF V(I,J)=2 THEN 1060
-# 1051 PRINT ":  ";
-# 1052 GOTO 1070
-# 1060 PRINT ":--";
-# 1070 NEXT I
-# 1071 PRINT "."
-# 1072 NEXT J
-# 1073 END
+# Add a random exit
+walls[height, (rand * width).round + 1] += 1
+
+# Print the maze
+draw_top(entry, width)
+(1..height).each do |row|
+  draw_row(walls[row])
+end

From e6f7975a6de13c4f68d68b5921cdb0f7190c9cd6 Mon Sep 17 00:00:00 2001
From: Marc Heiligers <marc@eternal.co.za>
Date: Sat, 6 Mar 2021 15:40:56 -0700
Subject: [PATCH 3/4] Refactor

---
 02 Amazing/ruby/amazing.rb | 298 ++++++++++++++++++++++---------------
 1 file changed, 176 insertions(+), 122 deletions(-)

diff --git a/02 Amazing/ruby/amazing.rb b/02 Amazing/ruby/amazing.rb
index c14148b1..d9a4f9d0 100644
--- a/02 Amazing/ruby/amazing.rb	
+++ b/02 Amazing/ruby/amazing.rb	
@@ -1,19 +1,15 @@
 # frozen_string_literal: true
 
-# Set up a constant hash for directions
-DIRECTIONS = {
-  left: 0,
-  up: 1,
-  right: 2,
-  down: 3
-}.freeze
+DEBUG = !ENV['DEBUG'].nil?
 
-EXIT_DOWN = 1
-EXIT_RIGHT = 2
+require 'io/console' if DEBUG
 
 # BASIC arrays are 1-based, unlike Ruby 0-based arrays,
-#   and this class simulates that. BASIC arrays are also zero-filled,
-#   which is also done here.
+# and this class simulates that. BASIC arrays are zero-filled,
+# which is also done here. While we could easily update the
+# algorithm to work with zero-based arrays, this class makes
+# the problem easier to reason about, row or col 1 are the
+# first row or column.
 class BasicArrayTwoD
   def initialize(rows, cols)
     @val = Array.new(rows) { Array.new(cols, 0) }
@@ -31,132 +27,190 @@ class BasicArrayTwoD
     @val[row - 1][col - 1] = n
   end
 
-  def to_s
-    @val.map { |row| row.join(' ') }.join("\n")
+  def to_s(width: max_width, row_hilite: nil, col_hilite: nil)
+    @val.map.with_index do |row, row_index|
+      row.map.with_index do |val, col_index|
+        if row_hilite == row_index + 1 && col_hilite == col_index + 1
+          "[#{val.to_s.center(width)}]"
+        else
+          val.to_s.center(width + 2)
+        end
+      end.join
+    end.join("\n")
+  end
+
+  def max_width
+    @val.flat_map { |row| row.map { |val| val.to_s.length } }.sort.last
   end
 end
 
-def draw_top(entry, width)
-  (1..width).each do |i|
-    if i == entry
-      print i == 1 ? '┏  ' : '┳  '
-    else
-      print i == 1 ? '┏━━' : '┳━━'
+class Maze
+  EXIT_DOWN = 1
+  EXIT_RIGHT = 2
+
+  # Set up a constant hash for directions
+  # The values represent the direction of the move as changes to row, col
+  # and the type of exit when moving in that direction
+  DIRECTIONS = {
+    left: { row: 0, col: -1, exit: EXIT_RIGHT },
+    up: { row: -1, col: 0, exit: EXIT_DOWN },
+    right: { row: 0, col: 1, exit: EXIT_RIGHT },
+    down: { row: 1, col: 0, exit: EXIT_DOWN }
+  }.freeze
+
+  attr_reader :width, :height, :used, :walls, :entry
+
+  def initialize(width, height)
+    @width = width
+    @height = height
+
+    @used = BasicArrayTwoD.new(height, width)
+    @walls = BasicArrayTwoD.new(height, width)
+
+    create
+  end
+
+  def draw
+    # Print the maze
+    draw_top(entry, width)
+    (1..height - 1).each do |row|
+      draw_row(walls[row])
     end
+    draw_bottom(walls[height])
   end
 
-  puts '┓'
-end
+  private
 
-def draw_row(row)
-  print '┃'
-  row.each { |val| print val < 2 ? '  ┃' : '   ' }
-  puts
-  row.each { |val| print val == 0 || val == 2 ? '┣━━' : '┃  ' }
-  puts '┫'
-end
+  def create
+    # entry represents the location of the opening
+    @entry = (rand * width).round + 1
 
+    # Set up our current row and column, starting at the top and the locations of the opening
+    row = 1
+    col = entry
+    c = 1
+    used[row, col] = c # This marks the opening in the first row
+    c += 1
 
-# 10 PRINT TAB(28);"AMAZING PROGRAM"
-# 20 PRINT TAB(15);"CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY"
-# 30 PRINT:PRINT:PRINT:PRINT
-puts ' ' * 28 + 'AMAZING PROGRAM'
-puts ' ' * 15 + 'CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY'
-puts "\n" * 3
+    while c != width * height + 1 do
+      debug walls, row, col
+      # remove possible directions that are blocked or
+      # hit cells that we have already processed
+      possible_dirs = DIRECTIONS.reject do |dir, change|
+        nrow = row + change[:row]
+        ncol = col + change[:col]
+        nrow < 1 || nrow > height || ncol < 1 || ncol > width || used[nrow, ncol] != 0
+      end.keys
 
-# 100 INPUT "WHAT ARE YOUR WIDTH AND LENGTH";H,V
-# 102 IF H<>1 AND V<>1 THEN 110
-# 104 PRINT "MEANINGLESS DIMENSIONS.  TRY AGAIN.":GOTO 100
-def ask_dimensions
-  print 'WHAT ARE YOUR WIDTH AND HEIGHT? '
-  width = gets.to_i
-  print '?? '
-  height = gets.to_i
-  [width, height]
-end
-
-width, height = ask_dimensions
-while width <= 1 || height <= 1
-  puts "MEANINGLESS DIMENSIONS.  TRY AGAIN."
-  width, height = ask_dimensions
-end
-
-# 110 DIM W(H,V),V(H,V)
-# BASIC programs can have the same variable names for different types,
-#   so the v array is not the same as the v int. Here we're renaming the arrays
-#   to have more friendly names
-used = BasicArrayTwoD.new(height, width)
-walls = BasicArrayTwoD.new(height, width)
-
-puts "\n" * 3
-
-
-# entry represents the location of the opening
-entry = (rand * width).round + 1
-
-# Set up our current row and column, starting at the top and the locations of the opening
-row = 1
-col = entry
-c = 1
-used[row, col] = c # This marks the opening in the first row
-c += 1
-
-while c != width * height + 1 do
-  # remove possible directions that are blocked or
-  # hit cells that we have already processed
-  possible_dirs = DIRECTIONS.keys
-  if col == 0 || used[row, col - 1] != 0
-    possible_dirs.delete(:left)
-  end
-  if row == 0 || used[row - 1, col] != 0
-    possible_dirs.delete(:up)
-  end
-  if col == width || used[row, col + 1] != 0
-    possible_dirs.delete(:right)
-  end
-  if row == height || used[row + 1, col] != 0
-    possible_dirs.delete(:down)
-  end
-
-  # If we can move in a direction, move and make opening
-  if possible_dirs.size != 0
-    direction = possible_dirs.sample # pick a random direction
-    if direction == :left
-      col = col - 1
-      walls[row, col] = EXIT_RIGHT
-    elsif direction == :up
-      row = row - 1
-      walls[row, col] = EXIT_DOWN
-    elsif direction == :right
-      walls[row, col] += EXIT_RIGHT
-      col = col + 1
-    elsif direction == :down
-      walls[row, col] += EXIT_DOWN
-      row = row + 1
-    end
-    used[row, col] = c
-    c = c + 1
-  # otherwise, move to the next used cell, and try again
-  else
-    while true do
-      if col != width
-        col += 1
-      elsif row != height
-        row += 1
-        col = 1
+      # If we can move in a direction, move and make opening
+      if possible_dirs.size != 0
+        direction = possible_dirs.sample
+        change = DIRECTIONS[direction] # pick a random direction
+        if %i[left up].include?(direction)
+          row += change[:row]
+          col += change[:col]
+          walls[row, col] = change[:exit]
+        else
+          walls[row, col] += change[:exit]
+          row += change[:row]
+          col += change[:col]
+        end
+        used[row, col] = c
+        c = c + 1
+      # otherwise, move to the next used cell, and try again
       else
-        row = col = 1
+        loop do
+          if col != width
+            col += 1
+          elsif row != height
+            row += 1
+            col = 1
+          else
+            row = col = 1
+          end
+          break if used[row, col] != 0
+          debug walls, row, col
+        end
       end
-      break if used[row, col] != 0
     end
+
+    # Add a random exit
+    walls[height, (rand * width).round] += 1
+  end
+
+  def draw_top(entry, width)
+    (1..width).each do |i|
+      if i == entry
+        print i == 1 ? '┏  ' : '┳  '
+      else
+        print i == 1 ? '┏━━' : '┳━━'
+      end
+    end
+
+    puts '┓'
+  end
+
+  def draw_row(row)
+    print '┃'
+    row.each.with_index do |val, col|
+      print val < 2 ? '  ┃' : '   '
+    end
+    puts
+    row.each.with_index do |val, col|
+      print val == 0 || val == 2 ? (col == 0 ? '┣━━' : '╋━━') : (col == 0 ? '┃  ' : '┫  ')
+    end
+    puts '┫'
+  end
+
+  def draw_bottom(row)
+    print '┃'
+    row.each.with_index do |val, col|
+      print val < 2 ? '  ┃' : '   '
+    end
+    puts
+    row.each.with_index do |val, col|
+      print val == 0 || val == 2 ? (col == 0 ? '┗━━' : '┻━━') : (col == 0 ? '┗  ' : '┻  ')
+    end
+    puts '┛'
+  end
+
+  def debug(walls, row, col)
+    return unless DEBUG
+
+    STDOUT.clear_screen
+    puts walls.to_s(row_hilite: row, col_hilite: col)
+    sleep 0.1
   end
 end
 
-# Add a random exit
-walls[height, (rand * width).round + 1] += 1
+class Amazing
+  def run
+    draw_header
 
-# Print the maze
-draw_top(entry, width)
-(1..height).each do |row|
-  draw_row(walls[row])
+    width, height = ask_dimensions
+    while width <= 1 || height <= 1
+      puts "MEANINGLESS DIMENSIONS.  TRY AGAIN."
+      width, height = ask_dimensions
+    end
+
+    maze = Maze.new(width, height)
+    puts "\n" * 3
+    maze.draw
+  end
+
+  def draw_header
+    puts ' ' * 28 + 'AMAZING PROGRAM'
+    puts ' ' * 15 + 'CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY'
+    puts "\n" * 3
+  end
+
+  def ask_dimensions
+    print 'WHAT ARE YOUR WIDTH AND HEIGHT? '
+    width = gets.to_i
+    print '?? '
+    height = gets.to_i
+    [width, height]
+  end
 end
+
+Amazing.new.run
\ No newline at end of file

From 1e56217a86131bdb03e28a29a577f370653b4d9a Mon Sep 17 00:00:00 2001
From: Marc Heiligers <marc@eternal.co.za>
Date: Sat, 6 Mar 2021 15:46:40 -0700
Subject: [PATCH 4/4] Add some notes to README

---
 02 Amazing/ruby/README.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/02 Amazing/ruby/README.md b/02 Amazing/ruby/README.md
index fb32811e..8bf7896b 100644
--- a/02 Amazing/ruby/README.md	
+++ b/02 Amazing/ruby/README.md	
@@ -1,3 +1,9 @@
 Original source downloaded [from Vintage Basic](http://www.vintage-basic.net/games.html)
 
 Conversion to [Ruby](https://www.ruby-lang.org/en/)
+
+Converted to Ruby (with tons of inspiration from the Python version) by @marcheiligers
+
+Run `ruby amazing.rb`.
+
+Run `DEBUG=1 ruby amazing.ruby` to see how it works (requires at least Ruby 2.7).