diff --git a/xxubin04/README.md b/xxubin04/README.md
index 8134ba4..42145d5 100644
--- a/xxubin04/README.md
+++ b/xxubin04/README.md
@@ -2,5 +2,5 @@
 
 | 차시 |    날짜    | 문제유형 | 링크 | 풀이 |
 |:----:|:---------:|:----:|:-----:|:----:|
-| 1차시 | 2023.10.27 |  BFS  | -  | - |
+| 1차시 | 2023.11.08 |  스택  | <a href="https://www.acmicpc.net/problem/28278">스택 2</a>  | https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/3 |
 ---
diff --git "a/xxubin04/\352\265\254\355\230\204/28278_stack2.py" "b/xxubin04/\352\265\254\355\230\204/28278_stack2.py"
new file mode 100644
index 0000000..8c72dc4
--- /dev/null
+++ "b/xxubin04/\352\265\254\355\230\204/28278_stack2.py"
@@ -0,0 +1,33 @@
+import sys
+
+n = int(sys.stdin.readline())
+stack = []
+
+for i in range(n):
+    num = sys.stdin.readline().split()
+
+    if num[0] == "1":
+        stack.append(num[-1])
+
+    elif num[0] == "2":
+        if len(stack) != 0:
+            print(stack.pop(-1))
+        else:
+            print(-1)
+
+    elif num[0] == "3":
+        print(len(stack))
+
+    elif num[0] == "4":
+        if len(stack) == 0:
+            print(1)
+        else:
+            print(0)
+
+    elif num[0] == "5":
+        if len(stack) != 0:
+            print(stack[-1])
+        else:
+            print(-1)
+    else:
+        break
\ No newline at end of file