74-tgyuuAn

tgyuuAn/README.md

@@ -80,4 +80,5 @@
 | 71차시 | 2024.08.20 |  다익스트라  | <a href="https://www.acmicpc.net/problem/24042">다익스트라</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/235
 | 72차시 | 2024.08.23 |  DFS + 트리  | <a href="https://www.acmicpc.net/problem/20188">등산 마니아</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/238
 | 73차시 | 2024.08.26 |  BFS  | <a href="https://www.acmicpc.net/problem/14324">Rain (Small)</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/239
+| 74차시 | 2024.08.30 |  BFS  | <a href="https://www.acmicpc.net/problem/11967">불 켜기</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/242
 ---

tgyuuAn/완전 탐색/불 켜기.py

@@ -0,0 +1,46 @@
+from collections import deque, defaultdict
+import sys
+
+def input(): return sys.stdin.readline().rstrip()
+
+N, M = map(int, input().split())
+board = [[False for _ in range(N+1)] for _ in range(N+1)]
+board[1][1] = True
+
+switch = defaultdict(list)
+
+for _ in range(M):
+    x, y, a, b = map(int, input().split())
+    switch[(x, y)].append((a,b))
+
+deq = deque()
+deq.append((1,1))
+dx = [0, 0, -1, 1]
+dy = [-1, 1, 0, 0]
+visited = {(1, 1),}
+dedicates = {(1, 1),}
+
+while deq:
+    now_x, now_y = deq.popleft()
+
+    for turn_on in switch[(now_x, now_y)]:
+        if turn_on not in dedicates:    # <<<------- 이 코드 한줄에 3시간 날림
+            dedicates.add(turn_on)
+
+            if turn_on in visited: 
+                deq.append(turn_on)
+
+    for dir in range(4):
+        new_x = now_x + dx[dir]
+        new_y = now_y + dy[dir]
+
+        if new_x <= 0 or new_x >= N+1: continue
+        if new_y <= 0 or new_y >= N+1: continue
+        if (new_x, new_y) in visited: continue
+
+        visited.add((new_x, new_y))
+
+        if (new_x, new_y) in dedicates:
+            deq.append((new_x, new_y))
+
+print(len(dedicates))