1 files changed, 46 insertions, 0 deletions
diff --git a/challenge-121/abigail/ruby/ch-2.rb b/challenge-121/abigail/ruby/ch-2.rb
new file mode 100644
index 0000000000..9696710e35
--- /dev/null
+++ b/challenge-121/abigail/ruby/ch-2.rb
@@ -0,0 +1,46 @@
+#!/usr/bin/ruby
+
+#
+# See ../README.md
+#
+ 
+#
+# Run as: ruby ch-2.rb < input-file
+#
+
+matrix = []
+
+def shortest_path (matrix, from, to, exclude)
+    if 1 + exclude . size() == matrix . length() then
+        return matrix [from] [to], [to]
+    end
+
+    shortest           = 99999999999
+    sh_path            = []
+    new_exclude        = exclude . clone()
+    new_exclude [from] = 1
+
+    for step in 0 .. matrix . length() - 1 do
+        if  step == from || step == to || exclude . key?(step) then
+            next
+        end
+
+        length, path = shortest_path(matrix, step, to, new_exclude)
+        if  shortest > length + matrix [from] [step] then
+            shortest = length + matrix [from] [step]
+            sh_path  = path . clone()
+            sh_path . unshift (step)
+        end
+    end
+
+    return shortest, sh_path
+end
+
+ARGF . each_line do
+    |line|
+    matrix . push (line . split(" ") . map {|x| x . to_i})
+end
+
+length, path = shortest_path(matrix, 0, 0, {})
+puts (length)
+puts (path . unshift(0) . join(" "))