1 files changed, 64 insertions, 0 deletions
diff --git a/13/2.lua b/13/2.lua
new file mode 100644
index 0000000..4af213c
--- /dev/null
+++ b/13/2.lua
@@ -0,0 +1,64 @@
+require "ext"
+local lines = {}
+for line in io.lines() do table.insert(lines,line) end
+
+local sum = 0
+local loaded = {{{6}},{{2}}}
+for i = 1,#lines,3 do
+	local l1,l2 = lines[i], lines[i+1]
+	l1 = l1:gsub("%[","{"):gsub("]","}")
+	l2 = l2:gsub("%[","{"):gsub("]","}")
+	l1 = load("return "..l1)()
+	l2 = load("return "..l2)()
+	table.insert(loaded,l1)
+	table.insert(loaded,l2)
+end
+
+local function compare(a,b) -- return true if a comes before b
+	assert(a ~= nil)
+	assert(b ~= nil)
+	if type(a) == "number" and type(b) == "number" then
+		if a < b then return true
+		elseif a > b then return false 
+		else return nil end
+	elseif type(a) == "table" and type(b) == "table" then
+		for i = 1,math.min(#a,#b) do
+			local result = compare(a[i],b[i]) 
+			if result ~= nil then
+				return result
+			end
+		end
+		if #a < #b then
+			return true
+		elseif #a > #b then
+			return false
+		else 
+			return nil
+		end
+	elseif type(a) == "number" and type(b) == "table" then
+		return compare({a},b)
+	elseif type(a) == "table" and type(b) == "number" then
+		return compare(a,{b})
+	end
+end
+table.sort(loaded,compare)
+local i2, i6
+for i = 1,#loaded do
+	local function eq(n)
+		return loaded[i] and
+		type(loaded[i]) == "table" and
+		#loaded[i] == 1 and
+		type(loaded[i][1]) == "table" and
+		#loaded[i][1] == 1 and
+		loaded[i][1][1] == n
+	end
+	if eq(6) then
+		print("Found 6 at ",i)
+		i6 = i
+	end
+	if eq(2) then
+		print("Found 2 at ",i)
+		i2 = i
+	end
+end
+print(i6 * i2)