day 8 part 1

day08/part1.lua

@@ -0,0 +1,21 @@
+#!/usr/bin/env luajit
+require("utils")
+
+function isunique(v)
+	return #v == 2 or #v == 3 or #v == 4 or #v == 7
+end
+
+local entries = {}
+local uniques = 0
+for line in io.lines(arg[3]) do
+	local words = split(line, " ")
+	local patterns = { unpack(words, 1, 10) }
+	local values = { unpack(words, 12, #words) }
+	table.insert(entries, {
+		patterns = patterns,
+		values = values,
+	})
+	uniques = uniques + count(values, isunique)
+end
+
+print(uniques)

utils.lua

@@ -23,3 +23,18 @@ function foreach(t, f)
 		t[k] = f(v)
 	end
 end
+
+function printtable(t)
+	for k, v in pairs(t) do
+		io.write(k..":"..v.." ")
+	end
+	io.write("\n")
+end
+
+function count(t, pred)
+	local count = 0
+	for k, v in pairs(t) do
+		if pred(v) then count = count + 1 end
+	end
+	return count
+end