Stack: 4.3

Author: daeseokyoun

README.md

@@ -41,4 +41,6 @@
 ### 연결리스트
 - [3.4 연결리스트 뒤집기](LinkedList/3_4_revert_list/README.md)
 - [3.5 순환 검출](LinkedList/3_5_cycle_detect/README.md)
-- [3.6 두 수 더하기](LinkedList/3_6_add_two_num/README.md)
+- [3.6 두 수 더하기](LinkedList/3_6_add_two_num/README.md)
+### 스택
+- [4.3 유효한 괄호 검증](Stack/4_3_valid_parentheses/README.md)

Stack/4_3_valid_parentheses/README.md

@@ -0,0 +1,12 @@
+## 유효한 괄호 검증
+- Page 223
+### Brute-force
+- [valid_parentheses_bf.py](valid_parentheses_bf.py)
+
+### LeetCode
+- https://leetcode.com/problems/valid-parentheses/
+
+
+
+
+

Stack/4_3_valid_parentheses/valid_parentheses_bf.py

@@ -0,0 +1,60 @@
+from typing import List
+
+tests = {
+    1: "()",
+    2: "()[]{}",
+    3: "(]",
+    4: "([)]",
+    5: "{[]}",
+    6: "(",
+    7: "]",
+    8: "((){})"
+}
+
+res = {
+    1: True,
+    2: True,
+    3: False,
+    4: False,
+    5: True,
+    6: False,
+    7: False,
+    8: True
+}
+
+def check_result(index: int, output: int):
+    if index > len(tests):
+        raise RuntimeError(f'Failed to get {index}th case')
+    return res.get(index, False) == output
+
+def isValid(s: str) -> bool:
+    stack = []
+
+    paren_map = {
+        ')': '(',
+        '}': '{',
+        ']': '['
+    }
+
+    for ch in s:
+        if ch not in paren_map.keys():
+            stack.append(ch)
+        else:
+            pair = stack.pop() if stack else ''
+
+            if paren_map[ch] != pair:
+                return False
+
+    return len(stack) == 0
+
+def main():
+    for index, input_string in tests.items():
+        res = isValid(input_string)
+
+        if check_result(index, res):
+            print(f'Test case {index} is correct: value {res}')
+        else:
+            print(f'Test case {index} is failed: value {res}')
+
+if __name__ == '__main__':
+    main()