1 files changed, 69 insertions, 0 deletions
diff --git a/challenge-210/roger-bell-west/lua/ch-2.lua b/challenge-210/roger-bell-west/lua/ch-2.lua
new file mode 100755
index 0000000000..635f55d792
--- /dev/null
+++ b/challenge-210/roger-bell-west/lua/ch-2.lua
@@ -0,0 +1,69 @@
+#! /usr/bin/lua
+
+-- by Michael Anderson at
+-- https://stackoverflow.com/questions/8722620/comparing-two-index-tables-by-index-value-in-lua
+function recursive_compare(t1,t2)
+   if t1==t2 then return true end
+   if (type(t1)~="table") then return false end
+   local mt1 = getmetatable(t1)
+   local mt2 = getmetatable(t2)
+   if( not recursive_compare(mt1,mt2) ) then return false end
+   for k1,v1 in pairs(t1) do
+      local v2 = t2[k1]
+      if( not recursive_compare(v1,v2) ) then return false end
+   end
+   for k2,v2 in pairs(t2) do
+      local v1 = t1[k2]
+      if( not recursive_compare(v1,v2) ) then return false end
+   end
+   return true
+end
+
+function numbercollision(aa)
+   local a = aa
+   local dirty = true
+   while dirty do
+      local b = {}
+      dirty = false
+      local i = 1
+      while i <= #a do
+         if i < #a and a[i] > 0 and a[i + 1] < 0 then
+            local ab = math.abs(a[i + 1])
+            if a[i] > ab then
+               table.insert(b, a[i])
+            elseif a[i] < ab then
+               table.insert(b, a[i + 1])
+            end
+            i = i + 2
+            dirty = true
+         else
+            table.insert(b, a[i])
+            i = i + 1
+         end
+      end
+      a = b
+   end
+   return a
+end
+
+if recursive_compare(numbercollision({2, 3, -1}), {2, 3}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+io.write(" ")
+
+if recursive_compare(numbercollision({3, 2, -4}), {-4}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+io.write(" ")
+
+if recursive_compare(numbercollision({1, -1}), {}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+print("")
+