AWK, Bash, Lua, Node.js, Perl, Python, Ruby solutions for week 116, part 1

1 files changed, 39 insertions, 0 deletions

diff --git a/challenge-116/abigail/lua/ch-1.lua b/challenge-116/abigail/lua/ch-1.lua
new file mode 100644
index 0000000000..df551a2e46
--- /dev/null
+++ b/challenge-116/abigail/lua/ch-1.lua
@@ -0,0 +1,39 @@
+#!/opt/local/bin/lua
+
+--
+-- See ../README.md
+--
+
+--
+-- Run as: lua ch-1.lua < input-file
+--
+
+function make_chain (string, start)
+    if   string == start
+    then return start
+    end
+    if   string : find ("^" .. start)
+    then tail   = string : sub (#start + 1, -1)
+         result = make_chain (tail, tostring (tonumber (start) + 1))
+         if   result ~= nil
+         then return start .. "," .. result
+         end
+         result = make_chain (tail, tostring (tonumber (start) - 1))
+         if   result ~= nil
+         then return start .. "," .. result
+         end
+    end
+    return nil
+end
+
+for line in io . lines () do
+    for i = 1, #line do
+        start  = line : sub (1, i)
+        result = make_chain (line, start)
+        if   result ~= nil
+        then print (result)
+             goto end_main
+        end
+    end
+    ::end_main::
+end