From fad5da2e2744c2c05630b325c9743dab763ff2af Mon Sep 17 00:00:00 2001
From: Felix Van der Jeugt <felix.vanderjeugt@posteo.net>
Date: Sun, 5 Dec 2021 12:10:59 +0100
Subject: [PATCH] add utils, use luajit which seems faster

---
 day04/part2.lua | 13 +------------
 day05/part2.lua | 17 +++++++----------
 prepare         |  4 +---
 run             |  5 +++++
 utils.lua       | 19 +++++++++++++++++++
 5 files changed, 33 insertions(+), 25 deletions(-)
 create mode 100755 run
 create mode 100644 utils.lua

diff --git a/day04/part2.lua b/day04/part2.lua
index 8338b93..cae1590 100644
--- a/day04/part2.lua
+++ b/day04/part2.lua
@@ -1,15 +1,4 @@
-function split(text, sep)
-	local parts = {}
-	local start = 0
-	local from, to = text:find(sep)
-	while from ~= nil do
-		table.insert(parts, text:sub(start, from - 1))
-		text = text:sub(to + 1)
-		from, to = text:find(sep)
-	end
-	table.insert(parts, text)
-	return parts
-end
+require("utils")
 
 local f = io.open(arg[3])
 local numbers = split(f:read("*l"), ",")
diff --git a/day05/part2.lua b/day05/part2.lua
index 5eeffe3..f1df3ac 100644
--- a/day05/part2.lua
+++ b/day05/part2.lua
@@ -1,3 +1,5 @@
+require("utils")
+
 function readline()
 	local x1 = io.read("*n")
 	io.read(1) -- ","
@@ -16,24 +18,19 @@ function mark(field, x, y)
 	field[x] = row
 end
 
-function sign(n)
-	if n == 0 then return 0
-	elseif n < 0 then return -1
-	else return 1
-	end
-end
+local input = io.open(arg[3]):read("*a")
+local lines = split(input, "\n")
 
-io.input(arg[3])
-local x1, y1, x2, y2 = readline()
 local field = {}
-while x1 ~= nil do
+for _, line in pairs(lines) do
+	local x1, y1, x2, y2 = unpack(split(line, "[^0-9]+"))
+	x1, y1, x2, y2 = tonumber(x1), tonumber(y1), tonumber(x2), tonumber(y2)
 	local x, y, dx, dy = x1, y1, sign(x2 - x1), sign(y2 - y1)
 	mark(field, x, y)
 	while x ~= x2 or y ~= y2 do
 		x, y = x + dx, y + dy
 		mark(field, x, y)
 	end
-	x1, y1, x2, y2 = readline()
 end
 
 local count = 0
diff --git a/prepare b/prepare
index ff04c7b..738fc5c 100755
--- a/prepare
+++ b/prepare
@@ -5,9 +5,7 @@ part="$2"
 day="$(printf '%02d' "$day")"
 
 if test -f "day${day}/part${part}.lua"; then
-	luac -o luac.out "day${day}/part${part}.lua"
-	printf '#!/bin/sh\nlua luac.out "$@"\n' > run
-	chmod u+x run
+	luajit -v >/dev/null
 elif test -f "day${day}/part${part}.hs"; then
 	#stack build
 	stack ghc -- -O3 "day${day}/part${part}.hs" -o run
diff --git a/run b/run
new file mode 100755
index 0000000..cd1f342
--- /dev/null
+++ b/run
@@ -0,0 +1,5 @@
+#!/bin/sh
+day="$1"
+part="$2"
+
+luajit "day${day}/part${part}.lua" "$@"
diff --git a/utils.lua b/utils.lua
new file mode 100644
index 0000000..94439b9
--- /dev/null
+++ b/utils.lua
@@ -0,0 +1,19 @@
+function split(text, sep)
+	local parts = {}
+	local start = 0
+	local from, to = text:find(sep)
+	while from ~= nil do
+		table.insert(parts, text:sub(start, from - 1))
+		text = text:sub(to + 1)
+		from, to = text:find(sep)
+	end
+	table.insert(parts, text)
+	return parts
+end
+
+function sign(n)
+	if n == 0 then return 0
+	elseif n < 0 then return -1
+	else return 1
+	end
+end