From 70a69ba86d10f98d13930b2764f1f0858cf0a056 Mon Sep 17 00:00:00 2001
From: aaron <aaron@duckpond.ch>
Date: Tue, 5 Dec 2023 16:23:06 +0100
Subject: [PATCH] add solution to day5

---
 5/fertilizer.py | 72 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)
 create mode 100644 5/fertilizer.py

diff --git a/5/fertilizer.py b/5/fertilizer.py
new file mode 100644
index 0000000..f2a637e
--- /dev/null
+++ b/5/fertilizer.py
@@ -0,0 +1,72 @@
+from aocd.models import Puzzle
+from aocd import submit
+from functools import reduce
+from operator import itemgetter
+
+import re
+
+
+def parse_almanac(data):
+    NUMBER_RE = re.compile(r"\d+")
+    stanzas = data.split("\n\n")
+    return [int(m.group(0)) for m in NUMBER_RE.finditer(stanzas[0])], [
+        sorted(
+            (
+                (nums[1], nums[1] + nums[2], nums[0] - nums[1])
+                for line in stanza.splitlines()
+                if len(nums := [int(m.group(0)) for m in NUMBER_RE.finditer(line)]) == 3
+            ),
+            key=itemgetter(0),
+        )
+        for stanza in stanzas[1:]
+    ]
+
+
+def remap_almanac(ranges, mappings):
+    for start, end in ranges:
+        for start2, end2, offset in mappings:
+            if start2 >= end or start >= end2:
+                continue
+            if start < start2:
+                yield start, start2
+                start = start2
+            end2 = min(end, end2)
+            yield start + offset, end2 + offset
+            start = end2
+        if start < end:
+            yield start, end
+
+
+def part_a(data):
+    seeds, mappings = parse_almanac(data)
+    return min(
+        map(itemgetter(0), reduce(remap_almanac, mappings, ((x, x + 1) for x in seeds)))
+    )
+
+
+def part_b(data):
+    seeds, mappings = parse_almanac(data)
+    return min(
+        map(
+            itemgetter(0),
+            reduce(
+                remap_almanac,
+                mappings,
+                ((x, x + y) for x, y in zip(*[iter(seeds)] * 2)),
+            ),
+        )
+    )
+
+
+if __name__ == "__main__":
+    # get puzzle and parse data
+    puzzle = Puzzle(year=2023, day=5)
+
+    answer_a = part_a(puzzle.input_data)
+    print(f"{answer_a}")
+    submit(answer_a, part="a", day=5, year=2023)
+
+    # part b:
+    answer_b = part_b(puzzle.input_data)
+    print(f"{answer_b}")
+    submit(answer_b, part="b", day=5, year=2023)