day 11 puzzle 2

progress.yaml

@@ -19,4 +19,4 @@
 10:
   stars: 2
 11:
-  stars: 1
+  stars: 2

src/day11/puzzle2.typ

@@ -0,0 +1,36 @@
+#import "/src/utils.typ": *
+
+#let process(rock, depth) = {
+  if depth == 0 {
+    return 1
+  }
+  if rock == 0 {
+    return process(1, depth - 1)
+  }
+  let rock-str = str(rock)
+  if calc.rem(rock-str.len(), 2) == 0 {
+    let hl = calc.div-euclid(rock-str.len(), 2)
+    let a = int(rock-str.slice(0, hl))
+    let b = int(rock-str.slice(hl))
+    return process(a, depth - 1) + process(b, depth - 1)
+  }
+  return process(rock * 2024, depth - 1)
+}
+
+#let solve(input) = {
+  let rocks = input.split(" ").map(int)
+  let total = 0
+  for rock in rocks {
+    total += process(rock, 75)
+  }
+  return total
+}
+
+#show-puzzle(
+  11, 2,
+  solve,
+  only-example: true
+)
+
+// Too long to recompile everytime
+#show-result(228651922369703)