diff --git a/백준/1111.py b/백준/1111.py
new file mode 100644
index 0000000..9cd831e
--- /dev/null
+++ b/백준/1111.py
@@ -0,0 +1,57 @@
+import sys
+
+input = sys.stdin.readline
+
+n = int(input())
+arr = list(map(int, input().split()))
+
+if(n==1):
+    print('A')
+elif(n==2):
+    print('A')
+elif(arr[1]==arr[0]):
+    flag = False
+    for i in range(1, n):
+        if(arr[i]!=arr[0]):
+            flag = True
+    if flag:
+        print('B')
+    else:
+        print(arr[0])
+elif(n>2 and arr[2]-arr[1] == arr[1]-arr[0]):
+    d = arr[1]-arr[0]
+    flag = False
+    for i in range(1, n):
+        if(arr[i]-arr[i-1]!=d):
+            flag = True
+    if flag:
+        print('B')
+    else:
+        print(arr[n-1]+d)
+elif(n>2 and arr[2]//arr[1] == arr[1]//arr[0]):
+    d = arr[1]//arr[0]
+    if(arr[1]/arr[0] < 1 and arr[1]*arr[0]<0):
+        print('B')
+        exit()
+    flag = False
+    for i in range(1, n):
+        if(arr[i]//arr[i-1]!=d):
+            flag = True
+    if flag:
+        print('B')
+    else:
+        print(arr[n-1]*d)
+else:
+    if (arr[1] - arr[0]) == 0:
+        print('B')
+        exit()
+    a = (arr[2] - arr[1]) // (arr[1] - arr[0])
+    b = (arr[2] + arr[1] - (arr[1] + arr[0]) * a) // 2
+    flag = False
+    for i in range(1, n):
+        if arr[i] != arr[i - 1] * a + b:
+            flag = True
+    if flag:
+        print('B')
+    else:
+        print(arr[n - 1] * a + b)
diff --git a/백준/1167.py b/백준/1167.py
new file mode 100644
index 0000000..d75492c
--- /dev/null
+++ b/백준/1167.py
@@ -0,0 +1,12 @@
+import sys
+
+V = sys.stdin.readline().rstrip()
+V = int(V)
+arr = [[] * V for i in range(V)]
+result = [V for i in range(V)]
+
+for i in range (V):
+    arr[i]=(list(map(int, input().split())))
+
+for i in range(V):
+    arr[i]=
diff --git a/백준/1238.py b/백준/1238.py
new file mode 100644
index 0000000..2795456
--- /dev/null
+++ b/백준/1238.py
@@ -0,0 +1,39 @@
+import sys
+import heapq
+
+sys.setrecursionlimit(10**6)
+input = sys.stdin.readline
+
+N, M, X = map(int, input().split()) # 학생수, 총 도로수, 가야하는 마을
+graph = [[] for i in range(N+1)]
+
+for _ in range(M):
+    a, b, c = map(int, input().split())
+    graph[a].append((b, c))
+
+
+def dijkstra(start):
+    dist = [sys.maxsize] * (N+1)
+    q = []
+    heapq.heappush(q, (0, start))
+    dist[start] = 0
+    while q:
+        distance, now = heapq.heappop(q)
+        if dist[now]<distance:
+            continue
+        for next in graph[now]:
+            cost = distance + next[1]
+            if cost < dist[next[0]]:
+                dist[next[0]] = cost
+                heapq.heappush(q, (cost, next[0]))
+    return dist
+
+#다익스트라 알고리즘 실행
+result_arr = []
+X_arr = dijkstra(X)
+
+for i in range(1, N+1):
+    y_arr = dijkstra(i)
+    result_arr.append(y_arr[X] + X_arr[i])
+
+print(max(result_arr))
\ No newline at end of file
diff --git a/백준/1256.Py b/백준/1256.Py
new file mode 100644
index 0000000..29a95a9
--- /dev/null
+++ b/백준/1256.Py
@@ -0,0 +1,29 @@
+import math
+import sys
+from itertools import permutations
+
+input = sys.stdin.readline
+
+N, M, K = map(int, input().split())
+
+total = math.comb(N+M, N)
+
+if K>total:
+    print(-1)
+else:
+    result = []
+    while N > 0 and M > 0:
+        count = math.comb(N+M-1, N-1)
+        if K<=count:
+            result.append('a')
+            N -= 1
+        else:
+            result.append('z')
+            M -= 1
+            K -= count
+    
+    result.extend(["a"] * N)
+    result.extend(["z"] * M)
+
+    print("".join(result))
+    
\ No newline at end of file
diff --git a/백준/1325.py b/백준/1325.py
new file mode 100644
index 0000000..41da918
--- /dev/null
+++ b/백준/1325.py
@@ -0,0 +1,27 @@
+import sys
+from collections import deque
+
+N, M = map(int, input().split())
+
+arr=[[] * N for i in range(N)]
+visited = [False] * (N+1)
+maxarr = [0] * (N+1)
+graph = dict()
+
+for i in range(M):
+    A, B = map(int, input().split())
+    graph[A] = B
+
+def DFS(graph, start):
+    visited.append(start)
+    for node in graph[start]:
+        if node not in visited:
+            DFS(graph, node, visited)
+    return visited
+
+DFS(graph, 1)
+
+
+
+
+