Add day 10 and day 9 solutions.

day9.cr

@@ -0,0 +1,36 @@
+require "./common.cr"
+
+lines = File.read("day9_input").split "\n"
+lines.pop
+
+players = 463
+last_points = 400
+
+marbles = [ 0 ]
+scores = Array(Int32).new(players, 0)
+player = 0
+pos = 0
+
+(last_points).times do |i|
+  i = i + 1
+  if (i % 23 == 0)
+    delete_at = (pos - 7 - marbles.size) % marbles.size
+
+    puts "current: #{i}"
+    puts "popping: #{marbles[delete_at]}"
+    scores[player] += i
+    scores[player] += marbles[delete_at]
+
+    pos = delete_at
+    marbles.delete_at delete_at
+  else
+    at = (pos + 2) % marbles.size
+    marbles.insert at, i
+    pos = marbles.index(i).not_nil!
+  end
+  
+  puts marbles
+  player = (player + 1) % players
+end
+
+puts scores.max