diff --git a/hadongun/README.md b/hadongun/README.md
index 0b54ed4..81fcc31 100644
--- a/hadongun/README.md
+++ b/hadongun/README.md
@@ -4,4 +4,8 @@
  |:----:|:---------:|:----:|:-----:|:----:|
  | 1차시 | 2024.10.01 |  구현  | [추억 점수](https://school.programmers.co.kr/learn/courses/30/lessons/176963)|https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/35|
  | 2차시 | 2025-03-21  | 그리디 알고리즘   | [로프] (https://www.acmicpc.net/problem/2217)
- | 3차시 | 2025-03-21  | 수학             | [보물] (https://www.acmicpc.net/problem/1026)
\ No newline at end of file
+ | 3차시 | 2025-03-21  | 수학             | [보물] (https://www.acmicpc.net/problem/1026)
+ | 4차시 | 2025-03-27  | 큐               | [카드2] (https://www.acmicpc.net/problem/2164)
+ | 5차시 | 2025-04-02  | 스택             | [스택2] (https://www.acmicpc.net/problem/28278)
+ | 6차시 | 2025-04-04  | 정렬             | [단어정렬](https://www.acmicpc.net/problem/1181)
+ | 7차시 | 2025-04-07  | 스택             | [균형잡힌 세상](https://www.acmicpc.net/problem/4949)
\ No newline at end of file
diff --git "a/hadongun/\354\212\244\355\203\235/\352\267\240\355\230\225\354\236\241\355\236\214 \354\204\270\354\203\201.py" "b/hadongun/\354\212\244\355\203\235/\352\267\240\355\230\225\354\236\241\355\236\214 \354\204\270\354\203\201.py"
new file mode 100644
index 0000000..399a313
--- /dev/null
+++ "b/hadongun/\354\212\244\355\203\235/\352\267\240\355\230\225\354\236\241\355\236\214 \354\204\270\354\203\201.py"	
@@ -0,0 +1,64 @@
+import sys
+while True:
+    charrr = sys.stdin.readline().rstrip()
+    if charrr == ".":
+        break
+    are_you_balanced = True
+    stack = []
+    for ch in charrr:
+        if ch == "(" or ch == "[":
+            stack.append(ch)
+        elif ch == ")":
+            if stack and stack[-1] == "(":
+                stack.pop()
+            else:
+                are_you_balanced = False
+                break
+        elif ch == "]":
+            if stack and stack[-1] == "[":
+                stack.pop()
+            else:
+                are_you_balanced = False
+                break
+    if are_you_balanced and not stack:
+        print("yes")
+    else:
+        print("no")
+
+'''import sys
+stack = []
+roundbalance = 0
+anglebalance = 0
+while True:
+    charrr = sys.stdin.readline().strip()
+    for ch in charrr:
+        stack.append(ch)
+    if charrr == "":
+        break
+    while stack:
+        if stack[-1] == "(":
+            roundbalance += 1
+            stack.pop()
+        elif stack[-1] == ")":
+            roundbalance -= 1
+            stack.pop()
+        elif stack[-1] == "[":
+            anglebalance += 1
+            stack.pop()
+        elif stack[-1] == "]":
+            anglebalance -= 1
+            stack.pop()
+        else:
+            stack.pop()
+        if len(stack) == 0:
+            break
+    if roundbalance == 0 and anglebalance == 0:
+        print("yes")
+    else:
+        print("no")'''
+        
+        
+            
+        
+    
+
diff --git "a/hadongun/\354\240\225\353\240\254/\353\213\250\354\226\264\354\240\225\353\240\254.py" "b/hadongun/\354\240\225\353\240\254/\353\213\250\354\226\264\354\240\225\353\240\254.py"
new file mode 100644
index 0000000..545bc63
--- /dev/null
+++ "b/hadongun/\354\240\225\353\240\254/\353\213\250\354\226\264\354\240\225\353\240\254.py"
@@ -0,0 +1,41 @@
+import sys
+
+def sort_word():
+    n = int(input())
+    unsorted_word = [sys.stdin.readline().strip() for _ in range(n)]
+    sorted_wording = set(unsorted_word)
+    sorted_word = sorted(sorted_wording, key = lambda x : (len(x), x))
+    for word in sorted_word:              
+        print(word)
+sort_word()
+
+
+"""
+시간 초과가 발생한 코드. 맞는 지는 모르겠습니다.
+def sort_word():
+    n = int(input())
+    unsorted_word = sys.stdin.read().splitlines()
+    for i in range(1, n):
+        key = len(unsorted_word[i])
+        j = i -1
+
+        while j >=0 and key < len(unsorted_word[j]):
+            if key == len(unsorted_word[j]):
+                if unsorted_word[i] == unsorted_word[j]:
+                    del unsorted_word[i]
+                if unsorted_word[j] > unsorted_word[i]:
+                    temp = unsorted_word[j]
+                    unsorted_word[j] = unsorted_word[i]
+            unsorted_word[j + 1] = unsorted_word[j]
+            unsorted_word[j] = unsorted_word[j]
+            j -= 1
+            
+        
+        
+        
+    print(unsorted_word)
+sort_word()"""
+                
+            
+        
+