wip day3 part2

day3/day3.py

@@ -1,11 +1,19 @@
-from typing import Tuple, List
+from typing import Tuple, List, Dict, Set
+from dataclasses import dataclass
+from collections import defaultdict
 
+@dataclass(frozen=True)
+class Item:
+    pos: Tuple[int, int]
+    symbol: str
 
 def browse_schema(schema):
     total_parts = 0
     buf = []
     max_row, max_col = len(schema), len(schema[0])
 
+    numbers: List[Item] = []
+
     for y in range(max_row):
         for x in range(max_col):
             item = schema[y][x]
@@ -14,62 +22,84 @@ def browse_schema(schema):
                 buf.append(item)
             elif buf:
                 # end of a number, do the engine part check
-                if buf:
-                    neighbors = get_neighbors((x, y), len(buf), schema)
-                    
-                    if is_engine_part(neighbors):
-                        part_number = int("".join(buf))
-                        total_parts += part_number
-                    
-                    buf.clear()  # reached end of a number, clear buffer
+                number = "".join(buf)
+                neighbors = get_neighbors((x, y), len(buf), schema)
+                start_pos = (x-len(number), y)
+                numbers.append(Item(start_pos, number))
+                
+                if is_engine_part(neighbors):
+                    total_parts += int(number)
+                
+                buf.clear()  # reached end of a number, clear buffer
 
     print(f"Part 1, sum of the parts numbers = {total_parts}")
+
+    gears: Dict[Tuple[int, int], Set[Item]] = defaultdict(set)
+    for y in range(max_row):
+        for x in range(max_col):
+            item = schema[y][x]
+            if item == "*":
+                print(f"* ({x}, {y})")
+                neighbors = [n for n in get_neighbors_of((x, y), schema) if n.symbol.isdigit()]
+                if (x, y) == (5, 8):
+                    breakpoint()
+
+                for neighbor in neighbors:
+                    neighboring_numbers = [n for n in numbers
+                        if y-1 <= n.pos[1] == y+1
+                        and n.pos[0] <= neighbor.pos[0] <= n.pos[0] + len(n.symbol)]
+                    gears[(x,y)] = gears[(x,y)].union(neighboring_numbers)
+    
+    # gears = { key: value for key, value in gears.items() if len(value) <= 2 }
+
+
+
     print(f"Part 2, sum of the gear ratios = TODO")
 
 
-def is_engine_part(neighbors: List[str]) -> bool:
+def is_engine_part(neighbors: List[Item]) -> bool:
     # get list of symbols (not '.', \n or a number)
-    symbols = filter(lambda x: not x.isnumeric() and not x in (".", "\n"), neighbors)
+    symbols = filter(lambda x: not x.symbol.isnumeric() and not x.symbol in (".", "\n"), neighbors)
     return next(symbols, None) is not None
 
 
-def get_neighbors(pos: Tuple[int, int], length: int,  schema: List[List[str]]) -> List[str]:
+def get_neighbors(pos: Tuple[int, int], length: int,  schema: List[List[str]]) -> List[Item]:
     x, y = pos
     start_x = x - length
-    neighbors = [get_neighbors_of_digit((x, y), schema) for x in range(start_x, x)]
+    neighbors = [get_neighbors_of((x, y), schema) for x in range(start_x, x)]
     neighbors = [item for sublist in neighbors for item in sublist]  # flatten list of list
     return neighbors
 
 
-def get_neighbors_of_digit(pos: Tuple[int, int], schema: List[List[str]]) -> List[str]:
+def get_neighbors_of(pos: Tuple[int, int], schema: List[List[str]]) -> List[Item]:
     max_row, max_col = len(schema), len(schema[0])
     x, y = pos
-    neighbors = []
+    neighbors: List[Item] = []
     
     # top
     if y-1 >= 0:
-        neighbors.append(schema[y-1][x])
+        neighbors.append(Item((x, y-1), schema[y-1][x]))
     # bottom:
     if y+1 < max_row:
-        neighbors.append(schema[y+1][x])
+        neighbors.append(Item((x, y+1), schema[y+1][x]))
     # left
     if x-1 >= 0:
-        neighbors.append(schema[y][x-1])
+        neighbors.append(Item((x-1, y), schema[y][x-1]))
     # right
     if x+1 < max_col:
-        neighbors.append(schema[y][x+1])
+        neighbors.append(Item((x+1, y), schema[y][x+1]))
     # top-left
     if y-1 >= 0 and x-1 >= 0:
-        neighbors.append(schema[y-1][x-1])
+        neighbors.append(Item((x-1, y-1), schema[y-1][x-1]))
     # top-right
     if y-1 >= 0 and x+1 < max_col:
-        neighbors.append(schema[y-1][x+1])
+        neighbors.append(Item((x+1, y-1), schema[y-1][x+1]))
     # bottom-left
     if y+1 < max_row and x-1 >= 0:
-        neighbors.append(schema[y+1][x-1])
+        neighbors.append(Item((x-1, y+1), schema[y+1][x-1]))
     # bottom-right
     if y+1 < max_row and x+1 < max_col:
-        neighbors.append(schema[y+1][x+1])
+        neighbors.append(Item((x+1, y+1), schema[y+1][x+1]))
 
     return neighbors