2024(8): easy peasy

2024/08/part2.py

@@ -0,0 +1,50 @@
+import numpy as np
+from part1 import *
+
+verbose = False
+
+if __name__ == "__main__":
+	m = load_map()
+	frequencies = np.unique(m)
+
+	antinodes = []
+
+	for f in frequencies:
+		# Emptiness is killing me.
+		if f == ".":
+			continue
+
+		# Find all antennas with the same frequency.
+		antennas = np.array(np.where(m == f)).T
+
+		# For each pair of antennas, find antinodes.
+		for i in range(len(antennas)):
+			for j in range(i + 1, len(antennas)):
+				a = antennas[i]
+				b = antennas[j]
+				
+				antinodes += [a, b]
+
+				diff_a = a - b
+				diff_b = b - a
+
+				# TODO: Is copy needed?
+				overtone = a.copy() + diff_a
+				while isValid(m.shape, overtone):
+					antinodes.append(overtone.copy())
+					overtone += diff_a
+				overtone = a.copy() - diff_a
+				while isValid(m.shape, overtone):
+					antinodes.append(overtone.copy())
+					overtone -= diff_a
+
+				overtone = b.copy() + diff_b
+				while isValid(m.shape, overtone):
+					antinodes.append(overtone.copy())
+					overtone += diff_b
+				overtone = b.copy() - diff_b
+				while isValid(m.shape, overtone):
+					antinodes.append(overtone.copy())
+					overtone -= diff_b
+
+	print(len(np.unique(antinodes,axis=0)))