Day 11 Part 1 (and theorically part 2 but too slow to run in a day)

Author: AlexZeGamer

Diff for: 2024/11/code.py

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+# Advent of Code 2024 - Day 11
+# https://adventofcode.com/2024/day/11
+# Author: Alexandre MALFREYT
+
+DEBUG = False
+
+with open('input.txt', 'r') as f:
+    stones = [int(x) for x in f.read().strip().split(' ')]
+
+# Part 1
+def simulate_blink_inplace(stones: list[int]) -> list[int]:
+    i = 0
+    print(f"Simulating blink on {stones}") if DEBUG else None
+    while i < len(stones):
+        print(f"i={i}, stones[i]={stones[i]}") if DEBUG else None
+        stone = stones[i]
+        stone_str = str(stone)
+        nb_digits = len(stone_str)
+        
+        if stone == 0:
+            print("  stone is 0") if DEBUG else None
+            stones[i] = 1
+
+        elif nb_digits % 2 == 0:
+            print("  nb_digits is even") if DEBUG else None
+            stones[i] = int(stone_str[:nb_digits//2])
+            stones.insert(i+1, int(stone_str[nb_digits//2:]))
+            print(f"  Inserted {stones[i+1]} at position {i+1}") if DEBUG else None
+            i += 1 # Skip the next stone since we just inserted a new one
+        
+        else:
+            print("  nb_digits is odd") if DEBUG else None
+            stones[i] = stone * 2024
+
+        i += 1
+
+def simulate_n_blinks_inplace(stones: list[int], nb_blinks: int, print_steps: bool = False) -> None:
+    print("Initial arrangement:") if print_steps else None
+    print(" ".join(str(x) for x in stones)) if print_steps else None
+    print() if print_steps else None
+    for i in range(nb_blinks):
+        print(f"Simulating blink {i+1}")
+        simulate_blink_inplace(stones)
+        print(f"After {i+1} blink{'s' if i > 0 else ''}:") if print_steps else None
+        print(" ".join(str(x) for x in stones)) if print_steps else None
+        print() if print_steps else None
+
+simulate_n_blinks_inplace(stones, 25)
+
+print(f'Part 1 : {len(stones)}')
+
+
+# Part 2
+total = 0
+
+simulate_n_blinks_inplace(stones, 75-25) # 75 blinks - 25 already done
+
+print(f'Part 2 : {len(stones)}')
+
+# Examples
+print("--- Examples ---")
+
+stones_example1 = [0, 1, 10, 99, 999]  # Example 1
+stones_example2 = [125, 17]  # Example 2
+
+print("Example 1:")
+simulate_n_blinks_inplace(stones_example1, 1, print_steps=True)
+assert stones_example1 == [1, 2024, 1, 0, 9, 9, 2021976]
+
+print("Example 2:")
+simulate_n_blinks_inplace(stones_example2, 6, print_steps=True)
+assert stones_example2 == [2097446912, 14168, 4048, 2, 0, 2, 4, 40, 48, 2024, 40, 48, 80, 96, 2, 8, 6, 7, 6, 0, 3, 2]

Diff for: 2024/11/input.txt

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+8793800 1629 65 5 960 0 138983 85629