solved(python): baekjoon 1786

Author: himitery

baekjoon/python/1786/__init__.py

@@ -0,0 +1,48 @@
+import sys
+
+read = lambda: sys.stdin.readline().rstrip()
+
+
+class Problem:
+    def __init__(self):
+        self.t, self.p = read(), read()
+        self.n, self.m = len(self.t), len(self.p)
+
+    def solve(self) -> None:
+        result = self.kmp_search(self.get_prefix_table())
+
+        print(len(result))
+        print(" ".join(map(str, result)))
+
+    def get_prefix_table(self) -> list[int]:
+        prefix_table, y = [0] * self.m, 0
+
+        for x in range(1, self.m):
+            while y > 0 and self.p[x] != self.p[y]:
+                y = prefix_table[y - 1]
+
+            if self.p[x] == self.p[y]:
+                y += 1
+                prefix_table[x] = y
+
+        return prefix_table
+
+    def kmp_search(self, prefix_table: list[int]) -> list[int]:
+        result, y = [], 0
+
+        for x in range(self.n):
+            while y > 0 and self.t[x] != self.p[y]:
+                y = prefix_table[y - 1]
+
+            if self.t[x] == self.p[y]:
+                y += 1
+
+                if y == self.m:
+                    result.append(x - self.m + 2)
+                    y = prefix_table[y - 1]
+
+        return result
+
+
+if __name__ == "__main__":
+    Problem().solve()

baekjoon/python/1786/main.py

@@ -0,0 +1,12 @@
+[
+  {
+    "input": [
+      "ABC ABCDAB ABCDABCDABDE",
+      "ABCDABD"
+    ],
+    "expected": [
+      "1",
+      "16"
+    ]
+  }
+]

baekjoon/python/1786/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()