20250814 baekjoon

code_study/Baekjoon/python/7576.py

@@ -0,0 +1,39 @@
+from collections import deque
+import sys
+
+input = sys.stdin.readline
+
+M, N = map(int, input().split())
+emptyCount = 0
+tomatoCount = 0
+visited = [[-1]*M for _ in range(N)]
+q = deque()
+
+for n in range(N) :
+    row = list(map(int, input().split()))
+    for m in range(M) :
+        tomato = row[m]
+        if tomato == 1 :
+            q.append((m,n))
+            visited[n][m] = 0
+            tomatoCount += 1
+        elif tomato == -1 :
+            visited[n][m] = -2
+            emptyCount += 1
+
+dm = [1,-1,0,0]
+dn = [0,0,1,-1]
+dayMax = 0
+
+while len(q):
+    cm, cn = q.popleft()
+    
+    for i in range(4) :
+        nm, nn = cm + dm[i], cn + dn[i]
+        if 0 <= nm < M and 0 <= nn < N and visited[nn][nm] == -1 :
+            q.append((nm,nn))
+            tomatoCount += 1
+            visited[nn][nm] = visited[cn][cm] + 1
+            dayMax = max(dayMax, visited[nn][nm])
+
+print(dayMax if tomatoCount + emptyCount == N*M else -1)