diff --git a/.DS_Store b/.DS_Store
index 9dca0ad..0e71c75 100644
Binary files a/.DS_Store and b/.DS_Store differ
diff --git a/pu2rile/README.md b/pu2rile/README.md
index 21d88bf..9e8c156 100644
--- a/pu2rile/README.md
+++ b/pu2rile/README.md
@@ -17,4 +17,5 @@
 | 13차시 | 2024.07.26 |  스택  | [후위 표기식](https://www.acmicpc.net/problem/1918)  | [#43](https://github.com/AlgoLeadMe/AlgoLeadMe-10/pull/43)
 | 14차시 | 2024.08.05 |  트리  | [이진 탐색 트리](https://www.acmicpc.net/problem/5639)  | [#45](https://github.com/AlgoLeadMe/AlgoLeadMe-10/pull/45)
 | 15차시 | 2024.08.15 |  트리  | [나무 탈출](https://www.acmicpc.net/problem/15900)  | [#48](https://github.com/AlgoLeadMe/AlgoLeadMe-10/pull/48)
-| 16차시 | 2024.09.15 |  그리디 알고리즘  | [신입 사원](https://www.acmicpc.net/problem/15900)  | [#51](https://github.com/AlgoLeadMe/AlgoLeadMe-10/pull/51)
\ No newline at end of file
+| 16차시 | 2024.09.15 |  그리디 알고리즘  | [신입 사원](https://www.acmicpc.net/problem/15900)  | [#51](https://github.com/AlgoLeadMe/AlgoLeadMe-10/pull/51)
+| 17차시 | 2024.09.24 |  문자열  | [콰트로치즈피자](https://www.acmicpc.net/problem/27964)  | [#54](https://github.com/AlgoLeadMe/AlgoLeadMe-10/pull/54)
\ No newline at end of file
diff --git "a/pu2rile/\353\254\270\354\236\220\354\227\264/\354\275\260\355\212\270\353\241\234\354\271\230\354\246\210\355\224\274\354\236\220.py" "b/pu2rile/\353\254\270\354\236\220\354\227\264/\354\275\260\355\212\270\353\241\234\354\271\230\354\246\210\355\224\274\354\236\220.py"
new file mode 100644
index 0000000..65fac95
--- /dev/null
+++ "b/pu2rile/\353\254\270\354\236\220\354\227\264/\354\275\260\355\212\270\353\241\234\354\271\230\354\246\210\355\224\274\354\236\220.py"
@@ -0,0 +1,15 @@
+toping = int(input())
+toping_lst = input().split()
+cheese_set = set()
+
+for cheese in toping_lst:
+    # 토핑 이름의 마지막 6글자가 Cheese인지 확인
+    # 치즈 토핑이 맞다면
+    if cheese[-6:] == 'Cheese':
+        # 집합에 치즈 이름 추가 (중복 자동 제거)
+        cheese_set.add(cheese)  
+
+if len(cheese_set) >= 4:    # 서로 다른 치즈가 4개 이상이면
+    print("yummy")
+else:
+    print("sad")
\ No newline at end of file