1 files changed, 77 insertions(+), 8 deletions(-)

M 11/puzzle_1.py

@@ 5,11 5,14 @@ cat input.txt | python puzzle_1.py
 """
 import sys
 
+
 def print_octopi(octopi):
     for row in octopi:
         for col in row:
             sys.stdout.write(f"{col} ")
         sys.stdout.write("\n")
+    sys.stdout.write("\n")
+
 
 if __name__ == "__main__":
     octopi = list(


@@ 18,17 21,83 @@ if __name__ == "__main__":
             sys.stdin.read().splitlines(),
         )
     )
-    print_octopi(octopi)
-    for step in range(1, 2 + 1):
-        print("step", step)
+    WIDTH = len(octopi[0])
+    HEIGHT = len(octopi)
+    flash_count = 0
+    for step in range(1, 100 + 1):
         # Increment energy levels
         octopi = list(
             map(lambda row: list(map(lambda energy: energy + 1, row)), octopi)
         )
         # Look for flashes
-        for row_index, row in enumerate(octopi):
-            for col_index, energy in enumerate(row):
-                if energy > 9:
-                    octopi[row_index][col_index] = 0
+        found_flashes = True
+        while found_flashes:
+            found_flashes = False
+            for row_index in range(HEIGHT):
+                for col_index in range(WIDTH):
+                    energy = octopi[row_index][col_index]
+                    if energy > 9:
+                        flash_count += 1
+                        found_flashes = True
+                        # Found flash
+                        # Set to -1 to not flash twice in a step
+                        # https://barretblake.dev/blog/2021/12/advent-of-code-day11/
+                        octopi[row_index][col_index] = -1
+
+                        # Increment surrounding octopi
+                        # NW
+                        if (
+                            row_index > 0
+                            and col_index > 0
+                            and octopi[row_index - 1][col_index - 1] > -1
+                        ):
+                            octopi[row_index - 1][col_index - 1] += 1
+                        # N
+                        if row_index > 0 and octopi[row_index - 1][col_index] > -1:
+                            octopi[row_index - 1][col_index] += 1
+                        # NE
+                        if (
+                            row_index > 0
+                            and col_index < (WIDTH - 1)
+                            and octopi[row_index - 1][col_index + 1] > -1
+                        ):
+                            octopi[row_index - 1][col_index + 1] += 1
+                        # E
+                        if (
+                            col_index < (WIDTH - 1)
+                            and octopi[row_index][col_index + 1] > -1
+                        ):
+                            octopi[row_index][col_index + 1] += 1
+                        # SE
+                        if (
+                            row_index < (HEIGHT - 1)
+                            and col_index < (WIDTH - 1)
+                            and octopi[row_index + 1][col_index + 1] > -1
+                        ):
+                            octopi[row_index + 1][col_index + 1] += 1
+                        # S
+                        if (
+                            row_index < (HEIGHT - 1)
+                            and octopi[row_index + 1][col_index] > -1
+                        ):
+                            octopi[row_index + 1][col_index] += 1
+                        # SW
+                        if (
+                            row_index < (HEIGHT - 1)
+                            and col_index > 0
+                            and octopi[row_index + 1][col_index - 1] > -1
+                        ):
+                            octopi[row_index + 1][col_index - 1] += 1
+                        # W
+                        if col_index > 0 and octopi[row_index][col_index - 1] > -1:
+                            octopi[row_index][col_index - 1] += 1
+
+        # Set -1's to 0's
+        octopi = list(
+            map(
+                lambda row: list(map(lambda energy: energy if energy >= 0 else 0, row)),
+                octopi,
+            )
+        )
 
-        print_octopi(octopi)
+    sys.stdout.write(str(flash_count))