[py] Port 2018_11

py/aoc/__init__.py

@@ -2,7 +2,7 @@ import sys
 import argparse
 from pathlib import Path
 
-from .y2018 import d01, d02, d03, d04, d05, d06, d07, d08, d09, d10
+from .y2018 import d01, d02, d03, d04, d05, d06, d07, d08, d09, d10, d11
 from .y2020 import d10
 from .y2021 import d14
 from .y2022 import d01, d02, d03, d04, d05, d06
@@ -18,6 +18,7 @@ DAYS = {
     "2018_08": y2018.d08.solve,
     "2018_09": y2018.d09.solve,
     "2018_10": y2018.d10.solve,
+    "2018_11": y2018.d11.solve,
     "2020_10": y2020.d10.solve,
     "2021_14": y2021.d14.solve,
     "2022_01": y2022.d01.solve,

py/aoc/y2018/d11.py

@@ -0,0 +1,78 @@
+# PART 1
+
+
+def nth_digit(num, pos):
+    # nth_digit(1234, 0) = 123[4] = 4
+    # nth_digit(1234, 2) = 1[2]34 = 2
+    # nth_digit(1234, 4) = [0]1234 = 0
+
+    pos += 1
+    s = ("{:0" + str(pos) + "}").format(num)  # UGLY!
+    n = s[-pos]
+    return int(n)
+
+
+def power_level(number, x, y):
+    rack_id = x + 10
+    level = rack_id * y
+    level += number
+    level *= rack_id
+    level = nth_digit(level, 2)  # 100-er digit
+    level -= 5
+    return level
+
+
+def init_grid(number):
+    grid = {}
+    for x in range(1, 300 + 1):
+        for y in range(1, 300 + 1):
+            grid[(x, y)] = power_level(number, x, y)
+    return grid
+
+
+def power_of_square(grid, x, y):
+    power = 0
+    for dx in range(3):
+        for dy in range(3):
+            power += grid[(x + dx, y + dy)]
+    return power
+
+
+def find_max_power(grid):
+    max_power = 0
+    max_coords = None
+
+    for x in range(1, 300 - 2 + 1):
+        for y in range(1, 300 - 2 + 1):
+            power = power_of_square(grid, x, y)
+            if power > max_power:
+                max_power = power
+                max_coords = (x, y)
+
+    return max_coords
+
+
+# PART 2
+
+
+def square_power(grid, x, y, size):
+    pass
+
+
+def max_square(grid):
+    max_power = 0
+    max_coords = None
+    max_size = None
+
+    for size in range(1, 300 + 1):
+        for x in range(1, 300 + 1 - (size - 1)):
+            for y in range(1, 300 + 1 - (size - 1)):
+                pass
+
+
+def solve(inputstr):
+    number = int(inputstr.strip())
+    grid = init_grid(number)
+    x, y = find_max_power(grid)
+    print(f"Part 1: {x},{y}")
+    print(f"Part 2: NYI")