Day 11 in Python

Author: mlukaszek

day11.py

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+import sys
+from collections import defaultdict
+from functools import reduce
+from operator import add
+
+def adjacent(i,j):
+    return ((i+1,j), (i-1,j), (i,j+1), (i,j-1), (i+1,j+1), (i-1,j-1), (i+1,j-1), (i-1,j+1))
+
+def in_range(i, j, size):
+    return 0 <= min(i, j) and max(i, j) < size
+
+def find_high_energy(levels):
+    return set([ location for location in levels if levels[location] > 9 ])
+
+def flash(levels, size):
+    for i in range(size):
+        for j in range(size):
+            levels[(i,j)] += 1
+    
+    flashing = find_high_energy(levels)
+    flashed = set()
+    while len(flashing - flashed):
+        for location in (flashing - flashed):
+            flashed.add(location)
+            i, j = location
+            for adj in adjacent(i,j):
+                ai, aj = adj
+                if in_range(ai, aj, size):
+                    levels[adj] += 1
+        flashing = find_high_energy(levels)
+
+    for location in flashed:
+        levels[location] = 0
+    return len(flashed)
+
+def flashesAfter(levels, size, steps):
+    return reduce(add, [ flash(levels, size) for _ in range(steps) ])
+
+def main(args = ()):
+    fileName = "day11.txt" if len(args) < 1 else args[0]
+
+    levels = defaultdict(int)
+    with open(fileName) as lines:
+        for j, row in enumerate(lines):
+            for i, energy in enumerate(row.strip()):
+                levels[(i,j)] = int(energy)
+    size = max(i+1, j+1)
+
+    steps = 100
+    print("Part 1:", flashesAfter(levels, size, steps))
+    
+    while not all([ levels[location] == 0 for location in levels ]):
+        flash(levels, size)
+        steps +=1 
+    print("Part 2:", steps)
+
+if __name__ == "__main__":
+    sys.exit(main(sys.argv[1:]))

day11.txt

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+5212166716
+1567322581
+2268461548
+3481561744
+6248342248
+6526667368
+5627335775
+8124511754
+4614137683
+4724561156

day11sample.txt

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+5483143223
+2745854711
+5264556173
+6141336146
+6357385478
+4167524645
+2176841721
+6882881134
+4846848554
+5283751526

day11sample2.txt

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+11111
+19991
+19191
+19991
+11111