diff --git a/DFS BFS/5-10.py b/DFS BFS/5-10.py
new file mode 100644
index 0000000..74179bf
--- /dev/null
+++ b/DFS BFS/5-10.py	
@@ -0,0 +1,34 @@
+N,M = map(int,input().split())
+
+lst = []
+for i in range(N):
+    lst.append(list(map(int,input())))
+
+cnt = 0
+
+#상하좌우
+dx = [-1,1,0,0]
+dy = [0,0,-1,1]
+
+def dfs(x,y):
+        #들른 곳 좌표
+        lst[x][y] = 1
+
+        #상하좌우 이동
+        for i in range(4):
+            lx = x + dx[i]
+            ly = y + dy[i]
+
+            #내부에 있을 때
+            if(lx >= 0 and lx < N and ly >= 0 and ly < M):
+                if (lst[lx][ly] == 0):
+                    dfs(lx,ly)
+
+
+for i in range(N):
+    for j in range(M):
+        if (lst[i][j] == 0):
+            dfs(i,j)
+            cnt += 1
+
+print(cnt)
\ No newline at end of file
diff --git a/DFS BFS/5-11.py b/DFS BFS/5-11.py
new file mode 100644
index 0000000..e65d65e
--- /dev/null
+++ b/DFS BFS/5-11.py	
@@ -0,0 +1,36 @@
+from collections import deque
+
+N,M = map(int,input().split())
+
+lst = []
+for i in range(N):
+    lst.append(list(map(int,input())))
+
+#상하좌우
+dx = [-1,1,0,0]
+dy = [0,0,-1,1]
+
+def bfs(x,y):
+    queue = deque()
+    queue.append((x,y))
+
+    #큐가 빌 때까지
+    while queue:
+        x,y = queue.popleft()
+
+        for i in range(4):
+            lx = x + dx[i]
+            ly = y + dy[i]
+
+            #내부 제한
+            if(lx < 0 or ly < 0 or lx >= N or ly >= M):
+                continue
+            if(lst[lx][ly] == 0):
+                continue
+            #첫 방문시 기록
+            if(lst[lx][ly] == 1):
+                lst[lx][ly] = lst[x][y] + 1
+                queue.append((lx,ly))
+    return lst[N-1][M-1]
+
+print(bfs(0,0))
\ No newline at end of file
diff --git a/Implementation/4-1.py b/Implementation/4-1.py
new file mode 100644
index 0000000..4cb403a
--- /dev/null
+++ b/Implementation/4-1.py
@@ -0,0 +1,29 @@
+n = int(input())
+
+###입력키 리스트 받기
+key = list(map(str,input().split()))
+
+x = 1
+y = 1
+
+for i in key:
+    ###사각형 크기보다 작을 때 수행
+    if(x < n and y < n):
+        if(i == "R"):
+            x += 1
+        elif(i == "L"):
+            x -= 1
+        elif(i == "U"):
+            y -= 1
+        elif(i == "D"):
+            y += 1
+    ###사각형 크기보다 크면 넘어가기
+    else:
+        continue
+    ###좌표가 0일 때 처리
+    if (x == 0):
+        x += 1
+    elif (y == 0):
+        y += 1
+
+print(y, x)
\ No newline at end of file
diff --git a/Implementation/4-2.py b/Implementation/4-2.py
new file mode 100644
index 0000000..b40f17b
--- /dev/null
+++ b/Implementation/4-2.py
@@ -0,0 +1,17 @@
+h = int(input())
+
+cnt = 0
+
+###h시간, 60분, 60초 동안 반복
+for i in range(h+1):
+    for j in range(60):
+        for k in range(60):
+            ###개수를 세기 위한 연산
+            if((i//10 == 3 or i%10 == 3)):
+                cnt += 1
+            elif((j//10 == 3 or j%10 == 3)):
+                cnt += 1
+            elif((k//10 == 3 or k%10 == 3)):
+                cnt += 1
+                
+print(cnt)
\ No newline at end of file
diff --git a/Implementation/4-3.py b/Implementation/4-3.py
new file mode 100644
index 0000000..04f72d7
--- /dev/null
+++ b/Implementation/4-3.py
@@ -0,0 +1,22 @@
+###체스판 좌표
+row = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']
+col = [1, 2, 3, 4 ,5, 6, 7, 8]
+
+data = list(input())
+
+###위치를 좌표화
+loc = [row.index(data[0]), col.index(int(data[1]))]
+
+###나이트가 이동하는 경우의 수
+mov = [[-2,-1], [-2,1], [2,1], [2,-1], [1,-2], [1,2], [-1,2], [-1,-2]]
+
+###더한 후 0보다 크면 카운트
+cnt = 0
+for x,y in mov:
+    x += loc[0]
+    y += loc[1]
+    
+    if (x > 0 and y > 0):
+        cnt += 1
+    
+print(cnt)
\ No newline at end of file
diff --git a/Implementation/4-4.py b/Implementation/4-4.py
new file mode 100644
index 0000000..5cf7f55
--- /dev/null
+++ b/Implementation/4-4.py
@@ -0,0 +1,55 @@
+N, M = map(int,input().split())
+x, y, d = map(int,input().split())
+
+###맵 입력
+maps = []
+for i in range(N):
+    maps.append(list(map(int,input().split())))
+
+###방향에 따른 이동
+dx = [-1,0,1,0]
+dy = [0,1,0,-1]
+
+###처음 위치 표시
+maps[x][y] = 1
+cnt = 1
+dir = 0
+
+while (1):
+    ###서쪽 바라보기 // 반복
+    d -= 1
+    if (d < 0):
+        d = 3
+    
+    ###이동 후 위치
+    lx = x + dx[d]
+    ly = y + dy[d]
+    
+    ###가보지 않은 곳
+    if (maps[lx][ly] == 0):
+        maps[lx][ly] = 1
+        
+        x = lx
+        y = ly
+        
+        cnt += 1
+        dir = 0
+        
+        continue
+    else:
+        dir += 1
+    
+    ###4방향 모두 가본 칸 or 바다
+    if(dir == 4):
+        lx = x - dx[d]
+        ly = y - dy[d]
+        
+        if(maps[lx][ly] == 0):
+            x = lx
+            y = ly
+            
+        else:
+            break
+      
+
+print(cnt)
\ No newline at end of file
diff --git a/Sort/6-10.py b/Sort/6-10.py
new file mode 100644
index 0000000..c1e4379
--- /dev/null
+++ b/Sort/6-10.py
@@ -0,0 +1,10 @@
+N = int(input())
+
+lst = []
+for i in range(N):
+    lst.append(int(input()))
+
+lst.sort(reverse = True)
+
+lst = list(map(str,lst))
+print(' '.join(lst))
\ No newline at end of file
diff --git a/Sort/6-11.py b/Sort/6-11.py
new file mode 100644
index 0000000..e2fe834
--- /dev/null
+++ b/Sort/6-11.py
@@ -0,0 +1,16 @@
+N = int(input())
+
+
+#리스트 입력
+lst = []
+
+for i in range(N):
+    data = input().split()
+    lst.append([data[0],int(data[1])])
+print(lst)
+
+lst.sort(key = lambda x : x[1])
+
+for i in lst:
+    print(i[0],end=' ')
+
diff --git a/Sort/6-12.py b/Sort/6-12.py
new file mode 100644
index 0000000..aa7b178
--- /dev/null
+++ b/Sort/6-12.py
@@ -0,0 +1,17 @@
+N, K = map(int,input().split())
+A = list(map(int,input().split()))
+B = list(map(int,input().split()))
+
+#리스트 정렬
+A.sort()
+B.sort(reverse = True)
+
+#비교 후 바꾸기
+for i in range(K):
+    if(A[i] < B[i]):
+        A[i] = B[i]
+    
+    else:
+        break
+
+print(sum(A))
\ No newline at end of file