Day 05

day05/part1.py

@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+from typing import List, Tuple
+
+lines = (x.strip() for x in open("input.txt"))
+seeds = ()
+current_map = "undef"
+maps = {}
+map_names = []
+
+for line in lines:
+    match line:
+        case "" | "\n":
+            continue
+        case x if x.startswith("seeds: "):
+            rest = x[len("seeds: "):]
+            seeds = tuple(int(y) for y in rest.split(" "))
+        case x if x.endswith(" map:"):
+            rest = x[:-len(" map:")]
+            current_map = rest
+            maps[current_map] = []
+            map_names.append(current_map)
+        case x if len(x) and x[0].isdigit():
+            maps[current_map].append(tuple(int(y) for y in x.split(" ")))
+        case _:
+            pass
+
+def parse_map(value: List[Tuple[int, int, int]]):
+    curr = 0
+    out = []
+    for dest, src, size in sorted(value, key=lambda x: x[1]):
+        if src > curr:
+            out.append((curr, 0))
+        if size > 0:
+            out.append((src, dest-src))
+        curr = src + size
+    out.append((curr, 0))
+    return out
+
+print(maps)
+maps = {name: parse_map(value) for name, value in maps.items()}
+print(maps)
+
+def find_largest_smaller_value(sorted_list, x):
+    low, high = 0, len(sorted_list)
+
+    while low < high - 1:
+        mid = (low + high) // 2
+        if sorted_list[mid][0] <= x:
+            low = mid
+        else:
+            high = mid
+
+    return sorted_list[low]
+
+result = float("inf")
+for seed in seeds:
+    for name in map_names:
+        seed += find_largest_smaller_value(maps[name], seed)[1]
+    result = min(seed, result)
+
+print(result)