diff --git a/tgyuuAn/README.md b/tgyuuAn/README.md
index 1739d158..3439e261 100644
--- a/tgyuuAn/README.md
+++ b/tgyuuAn/README.md
@@ -87,4 +87,5 @@
 | 78차시 | 2024.10.06 |  그리디  | <a href="https://school.programmers.co.kr/learn/courses/30/lessons/68646">풍선 터뜨리기</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/250
 | 79차시 | 2024.10.12 |  이분 매칭  | <a href="https://www.acmicpc.net/problem/9576">책 나눠주기</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/251
 | 80차시 | 2024.11.11 |  다익스트라  | <a href="https://www.acmicpc.net/problem/11779">최소비용 구하기 2</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/254
+| 81차시 | 2024.11.15 |  이분 탐색  | <a href="https://www.acmicpc.net/problem/1701">Cubeeditor</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/255
 ---
diff --git "a/tgyuuAn/\354\235\264\353\266\204 \355\203\220\354\203\211/Cubeeditor.py" "b/tgyuuAn/\354\235\264\353\266\204 \355\203\220\354\203\211/Cubeeditor.py"
new file mode 100644
index 00000000..630b1707
--- /dev/null
+++ "b/tgyuuAn/\354\235\264\353\266\204 \355\203\220\354\203\211/Cubeeditor.py"	
@@ -0,0 +1,28 @@
+from collections import defaultdict
+import sys
+
+def input(): return sys.stdin.readline().rstrip()
+
+_input = input()
+
+def check(string, mid):
+    temp = defaultdict(int)
+    for start_idx in range(len(string)-mid+1):
+        now = string[start_idx:start_idx+mid]
+        temp[now] += 1
+        if temp[now] >=2 : return True
+    return False
+
+answer = 0
+left = 0
+right = len(_input)
+while left+1 < right:
+    mid = (left+right)//2
+    
+    # 만약 해당 버퍼 크기에 답이 있다면
+    if check(_input, mid):
+        answer = mid
+        left = mid
+    else: right = mid
+    
+print(answer)
\ No newline at end of file