Advent of Code 2025 - Day 5 : Python version

advent_of_code/2025(python)/day5.py

@@ -0,0 +1,61 @@
+
+def solve_day5_part1(input_):
+
+    ranges = []
+    cnt = 0
+
+    for line in input_:
+        if line.strip() == "":
+            merged_ranges = _merge_intervals(ranges)
+            continue
+        if "-" in line:
+            start, end = map(int, line.split("-"))
+            # Process range
+            ranges.append([start, end])
+        else:
+            number = int(line)
+            # Process ingredients
+            for range in merged_ranges:
+                if range[0] <= number <= range[1]:
+                    cnt += 1
+
+    return cnt
+
+
+def _merge_intervals(intervals):
+    if not intervals:
+        return []
+
+    intervals.sort(key=lambda x: x[0])
+    res = [intervals[0]]
+    prev_end = intervals[0][1]
+    for current in intervals[1:]:
+        # no overlap
+        if current[0] > prev_end:
+            res.append(current)
+            prev_end = current[1]
+        else:
+        # with overlap, choose maximum end as new end
+            res[-1][1] = max(prev_end, current[1])
+            prev_end = res[-1][1]
+    return res
+
+
+def solve_day5_part2(input_):
+    ranges = []
+    cnt = 0
+
+    for line in input_:
+
+        cnt = 0
+        if "-" in line:
+            start, end = map(int, line.split("-"))
+            # Process range
+            ranges.append([start, end])
+
+        if line.strip() == "":
+            merged_ranges = _merge_intervals(ranges)
+            for range in merged_ranges:
+                cnt += (range[1]-range[0]+1)
+
+            return cnt

advent_of_code/2025(python)/test_day5.py

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+import unittest
+
+from day5 import solve_day5_part1, solve_day5_part2
+
+question_input = [
+    "3-5",
+    "10-14",
+    "16-20",
+    "12-18",
+    "",
+    "1",
+    "5",
+    "8",
+    "11",
+    "17",
+    "32",
+]
+
+
+class TestSample(unittest.TestCase):
+
+    def test_part1(self):
+        self.assertEqual(solve_day5_part1(question_input), 3)
+
+    def test_part2(self):
+        self.assertEqual(solve_day5_part2(question_input), 14)
+
+
+if __name__ == "__main__":
+    unittest.main()