Merge pull request #165 from AlgoLeadMe/46-tgyuuAn

46-tgyuuAn

tgyuuAn/README.md

@@ -47,4 +47,5 @@
 | 43차시 | 2024.03.10 |  이분 탐색  | <a href="https://school.programmers.co.kr/learn/courses/30/lessons/64062">징검다리 건너기</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/157
 | 44차시 | 2023.03.13 |  트라이  | <a href="https://www.acmicpc.net/problem/14725">개미굴</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/159
 | 45차시 | 2023.03.16 |  트라이  | <a href="https://www.acmicpc.net/problem/31413">트라이</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/162
+| 46차시 | 2023.03.20 |  트라이  | <a href="https://www.acmicpc.net/problem/27652">AB</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/165
 ---

tgyuuAn/트라이/AB.py

@@ -0,0 +1,80 @@
+import sys
+from collections import defaultdict
+
+class Node():
+    def __init__(self, key = None):
+        self.key = key
+        self.count = 0
+        self.children = {}
+
+class Tries():
+    def __init__(self):
+        self.head = Node(None)
+
+    def add(self, element):
+        now = self.head
+
+        for char in element:
+            if char not in now.children:
+                now.children[char] = Node(char)
+
+            now = now.children[char]
+            now.count += 1
+
+    def delete(self, element):
+        now = self.head
+
+        for char in element:
+            child = now.children[char]
+            child.count -= 1
+            if child.count == 0: del now.children[char]
+            now = child
+
+    def find(self, element):
+        now = self.head
+        dic = defaultdict(int)
+
+        string = ""
+        for char in element:
+            if char not in now.children: return dic
+
+            string = string + char
+            now = now.children[char]
+            dic[string] = now.count
+
+        return dic
+
+def input(): return sys.stdin.readline().rstrip()
+
+def query(method, target, element):
+    if method == "add": target.add(element)
+
+    if method == "delete": target.delete(element)
+
+    if method == "find":
+        n = len(element)
+        a_result = A.find(element)
+        b_result = B.find(element[::-1])
+
+        answer = 0
+        for a_len in range(1,n):
+            answer += a_result[element[:a_len]] * b_result[element[:a_len-1:-1]]
+
+        print(answer)
+
+N = int(input())
+A = Tries()
+B = Tries()
+method, target, element = "", "", ""
+
+for _ in range(N):
+    _input = input()
+    if _input[:4] == "find": 
+        method,element = _input.split()
+        query(method, A, element)
+
+    else:
+        method, target, element = _input.split()
+
+        if target == "A": query(method, A, element)
+        else: query(method, B, element[::-1])