solved(python): baekjoon 1766

Author: himitery

baekjoon/python/1766/__init__.py

@@ -0,0 +1,45 @@
+import heapq
+import sys
+from collections import defaultdict
+
+read = lambda: sys.stdin.readline().rstrip()
+
+
+class Problem:
+    def __init__(self):
+        self.n, self.m = map(int, read().split())
+        self.data, self.cached = defaultdict(set), [0 for _ in range(self.n + 1)]
+
+        for _ in range(self.m):
+            src, dest = map(int, read().split())
+            self.data[src].add(dest)
+            self.cached[dest] += 1
+
+    def solve(self) -> None:
+        queue, sequence = self.find_available(), []
+
+        while queue and len(sequence) < self.n:
+            if len(queue) == 0:
+                queue.extend(self.find_available())
+
+            num = heapq.heappop(queue)
+            sequence.append(num)
+
+            for next_num in sorted(self.data[num]):
+                self.cached[next_num] -= 1
+                if self.cached[next_num] == 0:
+                    heapq.heappush(queue, next_num)
+
+        print(*sequence)
+
+    def find_available(self) -> list[int]:
+        values = []
+        for num in range(1, self.n + 1):
+            if self.cached[num] == 0:
+                heapq.heappush(values, num)
+
+        return values
+
+
+if __name__ == "__main__":
+    Problem().solve()

baekjoon/python/1766/main.py

@@ -0,0 +1,12 @@
+[
+  {
+    "input": [
+      "4 2",
+      "4 2",
+      "3 1"
+    ],
+    "expected": [
+      "3 1 4 2"
+    ]
+  }
+]

baekjoon/python/1766/sample.json

@@ -0,0 +1,36 @@
+import json
+import os.path
+import unittest
+from io import StringIO
+from unittest.mock import patch
+
+from parameterized import parameterized
+
+from main import Problem
+
+
+def load_sample(filename: str):
+    path = os.path.join(os.path.dirname(os.path.abspath(__file__)), filename)
+
+    with open(path, "r") as file:
+        return [(case["input"], case["expected"]) for case in json.load(file)]
+
+
+class TestCase(unittest.TestCase):
+    @parameterized.expand(load_sample("sample.json"))
+    def test_case(self, case: str, expected: list[str]):
+        # When
+        with (
+            patch("sys.stdin.readline", side_effect=case),
+            patch("sys.stdout", new_callable=StringIO) as output,
+        ):
+            Problem().solve()
+
+            result = output.getvalue().rstrip()
+
+        # Then
+        self.assertEqual("\n".join(expected), result)
+
+
+if __name__ == "__main__":
+    unittest.main()