day 5 reverse bruteforce

python/README.md

@@ -1,10 +1,6 @@
 ToDo
 =====
 
-- Day 1 Part 2
-
-- Day 5 Part 2
-
 - Day 7 Part 2
 
 - Day 10 both parts

python/day5.py

@@ -68,15 +68,15 @@ def seed_is_valid(seed: int, seed_ranges: list[tuple]) -> bool:
     return False
 
 def rev_traverse(loc: int) -> int:
-    map_names = list(maps.keys()).reverse()
+    map_names = list(maps.keys())[::-1]
     for name in map_names:
         map_applied = False
         for l in maps[name]:
             if not map_applied:
-                if seed in range(l[0],l[0]+l[2]):
-                    seed = seed - l[0] + l[1]
+                if loc in range(l[0],l[0]+l[2]):
+                    loc = loc - l[0] + l[1]
                     map_applied = True
-    return seed
+    return loc
 
 
 maps = parsed_maps(lines)
@@ -84,78 +84,13 @@ seeds = parsed_seeds(lines)
 seed_ranges = parsed_seed_ranges(lines)
 
 print(f"Solution Part 1: {min(seeds_to_locations(seeds, maps))}")
-print(f"Solution Part 2: {min(min_loc_ranges)}")
-
 
-    """ yikes
+def find_lowest_valid_location(seed_ranges: list[tuple]) -> int:
+    for i in range(100000000):
+        seed = rev_traverse(i)
+        if seed_is_valid(seed, seed_ranges):
+            return i
+    return None
 
-def parsed_seed_ranges(lines: list[str]) -> list[tuple]:
-    seeds = [int(x) for x in lines[0].strip("\n")[6:].split()]
-    seed_ranges = []
-    for i in range(0, len(seeds), 2):
-        seed_ranges.append((seeds[i], seeds[i] + seeds[i+1]))
-    return seed_ranges
-
-def map_seed_range(seed_range: tuple, mapping: list[int]) -> tuple:
-    #returns transformed range for one map and remaining range(s) that were not affected
-    def apply_map(tup: tuple, mapping):
-        x = tup[0]
-        y = tup[1]
-        result = (x + l[0] - l[1], y + l[0] - l[1])
-        #print(f"mapped {tup, result}")
-        return result
-
-    mapped = []
-    remaining = seed_range
-    for l in mapping:
-        not_mapped = []
-        #print(f"l: {l}")
-        #print(f"source range from {l[1]} to {l[1] + l[2]}")
-        while len(remaining) > 0:
-            r = remaining.pop()
-            #print(f"-----r: {r}-----")
-            if r[0] == r[1]:
-                pass
-                #print("just delete, empty range")
-            else:
-                if r[1] <= l[1]:
-                    #print("not mapped")
-                    not_mapped.append(r)
-                elif r[0] >= l[1] + l[2]:
-                    #print("not mapped")
-                    not_mapped.append(r)
-                elif r[0] >= l[1] and r[1] <= l[1] + l[2]:
-                    mapped.append(apply_map(r, l))
-                elif r[0] < l[1] and r[1] <= l[1] + l[2]:
-                    mapped.append(apply_map((l[1], r[1]), l))
-                    not_mapped.append((r[0], l[1]))
-                    #print(f"remained: {(r[0], l[1])}")
-                elif r[0] >= l[1] and r[1] > l[1] + l[2]:
-                    mapped.append(apply_map((r[0], l[1] + l[2]), l))
-                    not_mapped.append((l[1] + l[2], r[1]))
-                    #print(f"remained: {(l[1] + l[2], r[1])}")
-                elif r[0] < l[1] and r[1] > l[1] + l[2]:
-                    not_mapped.append(apply_map((l[1], l[1] + l[2]), l))
-                    remaining.append((r[0], l[1]))
-                    #print(f"remained: {(r[0], l[1])}")
-                    remaining.append((l[1] + l[2], r[1]))
-                    #print(f"remained: {(l[1] + l[2], r[1])}")
-        #print(not_mapped)
-        remaining = list(set(not_mapped))
-        #print(f"remaining {remaining}")
-    return mapped + remaining
-
-
-def seed_range_to_loc_ranges(seed_ranges: list[tuple], maps: dict) -> list[tuple]:
-    # single seed range going through maps
-    #print(seed_ranges)
-    map_names = list(maps.keys())
-    for name in map_names:
-        #print(f"apply {name}")
-        seed_ranges = map_seed_range(seed_ranges, maps[name])
-        #print(seed_ranges)
-    return seed_ranges
-    
-#loc_ranges = seed_range_to_loc_ranges(parsed_seed_ranges(lines), maps)
-#min_loc_ranges = [x for x, y in loc_ranges]
-    """
+print(f"Solution to Part 2 takes a couple of minutes.")
+print(f"Solution Part 2: {find_lowest_valid_location(seed_ranges)}")