diff --git a/백준/3029.py b/백준/3029.py
new file mode 100644
index 0000000..55201ff
--- /dev/null
+++ b/백준/3029.py
@@ -0,0 +1,38 @@
+a=input()
+b=input()
+
+ahour=int(a[0:2])
+bhour=int(b[0:2])
+
+amin=int(a[3:5])
+bmin=int(b[3:5])
+
+asec=int(a[6:8])
+bsec=int(b[6:8])
+
+if(bsec<asec):
+    bsec+=60
+    amin+=1
+
+sec = bsec - asec
+
+if(bmin<amin):
+    bmin+=60
+    ahour+=1
+
+min = bmin - amin
+
+hour = bhour - ahour
+if(hour<0):
+    hour+=24
+
+if(hour == 0 and min == 0 and sec == 0):
+    hour=24
+
+
+sec = '{0:02d}'.format(sec)
+min = '{0:02d}'.format(min)
+hour = '{0:02d}'.format(hour)
+
+
+print(hour+ ":" + min + ":" + sec)
\ No newline at end of file
diff --git a/백준/3663.py b/백준/3663.py
new file mode 100644
index 0000000..302ebd9
--- /dev/null
+++ b/백준/3663.py
@@ -0,0 +1,26 @@
+import sys
+sys.setrecursionlimit(10**6)
+
+def controller(name):
+    def vertical(char):
+        diff = ord(char) - ord('A')  
+        return min(diff, 26 - diff)
+    
+    total_vertical = sum(vertical(i) for i in name)
+    min_move=1001
+    len_name=len(name)
+    min_horizon=len_name- 1
+    for i in range(len_name):
+        cumu = i + 1
+        while cumu < len_name and name[cumu] == 'A':
+            cumu +=1
+        move = min (2*(len_name-cumu)+i, min_horizon, 2*i+(len_name-cumu))
+        min_move = min(min_move , move)
+    
+    return min_move + total_vertical
+
+N = int(input())
+for _ in range(N):
+    temp = input().rstrip()
+    print(controller(temp))
+    
\ No newline at end of file
diff --git a/백준/4796.py b/백준/4796.py
new file mode 100644
index 0000000..41df2d7
--- /dev/null
+++ b/백준/4796.py
@@ -0,0 +1,13 @@
+case_num = 1
+
+while True:
+    L, P, V = map(int, input().split())
+    if (L==0 and P==0 and V==0):
+        break
+    tot = 0
+    week = V//P
+    remainder = V % P
+    result = week * L + min(remainder, L)
+    print(f"Case {case_num}: {result}")
+    case_num += 1
+
diff --git a/백준/9251.py b/백준/9251.py
new file mode 100644
index 0000000..81946e8
--- /dev/null
+++ b/백준/9251.py
@@ -0,0 +1,24 @@
+import sys
+
+input = sys.stdin.readline
+
+N = list(map(str, input().strip()))
+M = list(map(str, input().strip()))
+
+len_N = len(N)
+len_M = len(M)
+
+arr = [[0 for i in range(len_N+1)] for j in range(len_M+1)]
+
+tot = 0
+i=0
+j=0
+
+for j in range(1, len_M+1):
+    for i in range(1, len_N+1):
+        if(N[i-1] == M[j-1]):
+            arr[j][i] = arr[j-1][i-1] + 1
+        else:
+            arr[j][i] = max(arr[j][i-1], arr[j-1][i])
+
+print(arr[len_M][len_N])
\ No newline at end of file
diff --git a/백준/9252.py b/백준/9252.py
new file mode 100644
index 0000000..916d5dd
--- /dev/null
+++ b/백준/9252.py
@@ -0,0 +1,44 @@
+import sys
+
+input = sys.stdin.readline
+sys.setrecursionlimit(10**6)
+
+A = list(map(str, input().rstrip()))
+B = list(map(str, input().rstrip()))
+
+len_A = len(A)
+len_B = len(B)
+
+arr = [[0 for i in range(len_B+1)] for j in range(len_A+1)]
+
+for i in range(1, len_A+1):
+    for j in range(1, len_B+1):
+        if(A[i-1] == B[j-1]):
+            arr[i][j] = arr[i-1][j-1] + 1
+        else:
+            arr[i][j] = max(arr[i-1][j], arr[i][j-1])
+
+print(arr[len_A][len_B])
+
+#LCS 구현 방법
+result = []
+
+def getText(r, c):
+    if r==0 or c==0:
+        return
+    if A[r-1] == B[c-1]:
+        result.append(A[r-1])
+        getText(r-1, c-1)
+    else:
+        if arr[r-1][c] > arr[r][c-1]:
+            getText(r-1,c)
+        else:
+            getText(r, c-1)
+
+getText(len_A, len_B)
+result_reverse = []
+
+for i in range(len(result)):
+    result_reverse.append(result.pop())
+
+print(('').join(result_reverse))