105차 1번 문제풀이

Author: hangyeol

live10/test105/문제1/백한결.py

@@ -0,0 +1,36 @@
+import sys
+from collections import defaultdict, deque
+
+def main():
+    input = sys.stdin.readline
+
+    N, M, K, X = map(int, input().split())
+    graph = defaultdict(list)
+
+    for _ in range(M):
+        A, B = map(int, input().split())
+        graph[A].append(B)
+
+    distance = [-1] * (N + 1)
+    distance[X] = 0
+
+    queue = deque([X])
+
+    while queue:
+        current = queue.popleft()
+
+        for neighbor in graph[current]:
+            if distance[neighbor] == -1:
+                distance[neighbor] = distance[current] + 1
+                queue.append(neighbor)
+
+    result = [i for i in range(1, N + 1) if distance[i] == K]
+
+    if result:
+        for city in sorted(result):
+            print(city)
+    else:
+        print(-1)
+
+if __name__ == "__main__":
+    main()