Solve day 9

advent_of_code/oasis.py

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+"Day 9: Mirage Maintenance"
+
+Sequence = tuple[int, ...]
+
+
+def parse_sequence(desc: str) -> Sequence:
+    return tuple(int(num) for num in desc.split(" "))
+
+
+def extrapolate_sequence(sequence: tuple[int, ...]) -> int:
+    if any(sequence):
+        difference_sequence = tuple(
+            right - left for left, right in zip(sequence, sequence[1:])
+        )
+        next_difference = extrapolate_sequence(difference_sequence)
+        return sequence[-1] + next_difference
+    return 0
+
+
+def solve_part_1(input: str) -> int:
+    sequences = (parse_sequence(desc) for desc in input.split("\n"))
+    return sum(extrapolate_sequence(sequence) for sequence in sequences)
+
+
+def solve_part_2(input: str) -> int:
+    sequences = (parse_sequence(desc) for desc in input.split("\n"))
+    reversed_sequences = (tuple(reversed(sequence)) for sequence in sequences)
+    return sum(extrapolate_sequence(sequence) for sequence in reversed_sequences)