Update code to use advent lib.

day1.cr

@@ -1,4 +1,5 @@
-INPUT = File.read("day1.txt").lines.map(&.chomp.to_i32) 
+require "advent"
+INPUT = input(2020, 1).lines.map(&.chomp.to_i32) 
 
 def part1
   input = INPUT.clone.sort!

day2.cr

@@ -1,4 +1,5 @@
-INPUT = File.read("day2.txt").lines.map(&.chomp) 
+require "advent"
+INPUT = input(2020, 2).lines.map(&.chomp) 
 
 def parse(line)
     data = line.match(/([0-9]+)-([0-9]+) ([a-z]): ([a-z]+)/) 

day3.cr

@@ -1,4 +1,5 @@
-INPUT = File.read("day3.txt").lines.map(&.chomp) 
+require "advent"
+INPUT = input(2020, 3).lines.map(&.chomp) 
 
 def run(input, slopes)
   prod = 1_i64

day4.cr

@@ -1,5 +1,6 @@
 require "./passports.cr"
-INPUT = File.read("day4.txt")
+require "advent"
+INPUT = input(2020, 4)
 
 def part1
   input = INPUT.clone

day5.cr

@@ -1,4 +1,5 @@
-INPUT = File.read("day5.txt").lines.map(&.chomp) 
+require "advent"
+INPUT = input(2020, 5).lines.map(&.chomp) 
 
 def partition(choices, list)
   b = 0

day5g.cr

@@ -0,0 +1,2 @@
+i=File.read_lines("day5.txt").map &.tr("FBLR", "0101").to_i32(2);
+puts({i.max,(i.min..i.max).select{|n|!i.includes? n}})

template.cr

@@ -1,4 +1,5 @@
-INPUT = File.read("dayN.txt")#.lines.map(&.chomp) 
+require "advent"
+INPUT = input(2020, n)#.lines.map(&.chomp) 
 
 def part1
   input = INPUT.clone