solved(python): baekjoon 1918

Author: himitery

baekjoon/python/1918/__init__.py

@@ -0,0 +1,37 @@
+import sys
+
+read = lambda: sys.stdin.readline().rstrip()
+
+
+class Problem:
+    def __init__(self):
+        self.data = read()
+        self.precedence = {"+": 1, "-": 1, "*": 2, "/": 2}
+
+    def solve(self) -> None:
+        stack, output = [], ""
+
+        for word in self.data:
+            if word.isalpha():
+                output += word
+                continue
+
+            if word == "(":
+                stack.append(word)
+            elif word == ")":
+                while stack and stack[-1] != "(":
+                    output += stack.pop()
+                stack.pop()
+            else:
+                while stack and stack[-1] != "(" and self.precedence[stack[-1]] >= self.precedence[word]:
+                    output += stack.pop()
+                stack.append(word)
+
+        while stack:
+            output += stack.pop()
+
+        print(output)
+
+
+if __name__ == "__main__":
+    Problem().solve()

baekjoon/python/1918/main.py

@@ -0,0 +1,34 @@
+[
+  {
+    "input": [
+      "A*(B+C)"
+    ],
+    "expected": [
+      "ABC+*"
+    ]
+  },
+  {
+    "input": [
+      "A+B"
+    ],
+    "expected": [
+      "AB+"
+    ]
+  },
+  {
+    "input": [
+      "A+B*C"
+    ],
+    "expected": [
+      "ABC*+"
+    ]
+  },
+  {
+    "input": [
+      "A+B*C-D/E"
+    ],
+    "expected": [
+      "ABC*+DE/-"
+    ]
+  }
+]

baekjoon/python/1918/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()