감시 풀이

Author: saebyeok0306

BAEKJOON/3Gold/감시.py

@@ -0,0 +1,82 @@
+# 
+# https://www.acmicpc.net/problem/15683
+
+"""
+6 6
+0 0 0 0 0 0
+0 2 0 0 0 0
+0 0 0 0 6 0
+0 6 0 0 2 0
+0 0 0 0 0 0
+0 0 0 0 0 5
+"""
+
+import sys
+from itertools import product
+
+input = sys.stdin.readline
+N,M = map(int, input().split())
+board = [list(map(int, input().split())) for _ in range(N)]
+
+# L,U,R,D
+directions = [(-1,0),(0,-1),(1,0),(0,1)]
+cctv_direction = {
+    1: [0,1,2,3],
+    2: [0,1],
+    3: [0,1,2,3],
+    4: [0,1,2,3],
+    5: [0]
+}
+cctv_direction_details = {
+    1: [[0],[1],[2],[3]],
+    2: [[0,2],[1,3]],
+    3: [[0,1],[1,2],[2,3],[3,0]],
+    4: [[0,1,2],[1,2,3],[2,3,0],[3,0,1]],
+    5: [[0,1,2,3]]
+}
+
+empty = 0
+cctv_list = []
+for n in range(N):
+    for m in range(M):
+        if 1 <= board[n][m] <= 5:
+            cctv_list.append((board[n][m], n, m))
+        elif board[n][m] == 0:
+            empty += 1
+
+def stop_point(x, y):
+    if x < 0 or x >= N:
+        return True
+    if y < 0 or y >= M:
+        return True
+    return False
+
+answer = 64
+for cid, case in enumerate(product(*[cctv_direction[cctv_list[i][0]] for i in range(len(cctv_list))])):
+    empty_ = empty
+    cid += 7
+
+    # case 안에서의 각 cctv 방향
+    for idx, dirs in enumerate(case):
+        cctv,cx,cy = cctv_list[idx]
+
+        for direct in cctv_direction_details[cctv][dirs]:
+            nx,ny = cx,cy
+            while True:
+                dx,dy = directions[direct]
+                nx += dx
+                ny += dy
+
+                if stop_point(nx,ny) or board[nx][ny] == 6:
+                    break
+                if 1 <= board[nx][ny] <= 5:
+                    continue
+                if board[nx][ny] != cid:
+                    board[nx][ny] = cid
+                    empty_ -= 1
+
+    answer = min(empty_, answer)
+    if answer == 0:
+        break
+
+print(answer)