solution for day 9

1 files changed, 33 insertions, 0 deletions

diff --git a/day9.py b/day9.py
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+++ b/day9.py
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+#!/usr/bin/env python
+
+import numpy as np
+from scipy.ndimage import label
+
+with open("day9.txt") as data:
+    depthmap = []
+    for line in data:
+        row = [int(num) for num in line.strip()]
+        depthmap.append(row)
+    depthmap = np.array(depthmap)
+
+# part 1
+# convolve across grid
+
+def conv_filter(position: (int, int)) -> int:
+    def neighbors():
+        x, y = position
+        neighboring = {(x-1, y), (x+1, y), (x, y-1), (x, y+1)}
+        return {(xPos, yPos) for xPos, yPos in neighboring if 0 <= xPos <= depthmap.shape[0]-1 and 0 <= yPos <= depthmap.shape[1]-1}
+
+    if all(depthmap[position] < depthmap[pos] for pos in neighbors()):
+        return depthmap[position] + 1
+    else:
+        return 0
+
+print(sum(conv_filter((x, y)) for x in range(depthmap.shape[0]) for y in range(depthmap.shape[1])))
+
+# part 2
+basins, num_basins = label(depthmap != 9)
+counts = [np.count_nonzero(basins == num) for num in range(1, num_basins + 1)]
+counts.sort()
+print(np.prod(counts[-3:]))