승연 책 숙제(6/1/화) (#80)

* 특정 거리의 도시 찾기

* 연구소

* 경쟁적 전염

* 경쟁적 전염 fix

* 경쟁적 전염 fix

* Delete 17179.py

Author: dia312

syheo/codingTest1/13-15-특정 거리의 도시 찾기.py

@@ -0,0 +1,41 @@
+#CH13 BFSDFS기출
+#예제 13-15
+#특정거리의 도시찾기
+#백준 18352
+#실버 2 
+
+from collections import deque
+import sys
+input = sys.stdin.readline
+
+N,M,K,X = map(int,input().split())
+
+edges = [[] for _ in range(N+1)]
+visited = [False for _ in range(N+1)]
+#간선 정보 입력 받기
+for i in range(M):
+    a,b = map(int,input().split())
+    edges[a].append(b)
+
+def bfs():
+    answer = []
+    q = deque([])
+    q.append((X,0)) #현재노드, 이동 거리 
+    visited[X]=True
+    while q:
+        node, cnt = q.popleft()
+        if cnt==K:
+            answer.append(node)
+        for next in edges[node]:
+            if not visited[next]:
+                q.append((next,cnt+1))
+                visited[next]=True
+    return answer 
+
+result = bfs()
+result.sort()
+if len(result)==0:
+    print(-1)
+else:
+    for res in result:
+        print(res)

syheo/codingTest1/13-16-연구소.py

@@ -0,0 +1,73 @@
+#CH13 BFSDFS기출
+#예제 13-16
+#연구소
+#백준 14502
+#골드 5
+
+import itertools
+from collections import deque
+
+N , M = map(int,input().split())
+dx = [0,0,1,-1]
+dy = [1,-1,0,0]
+maps = []
+virus = []
+empties = []
+wall = 0
+whole_visited = [[False]*M for _ in range(N)]
+
+for i in range(N):
+    tmp = list(map(int,input().split()))
+    for j in range(M):
+        if tmp[j]==2:
+            virus.append((i,j))
+        elif tmp[j]==0:
+            empties.append((i,j))
+    maps.append(tmp)
+
+wall = N*M-len(virus)-len(empties)
+
+def bfs():
+
+    visited = [[False]*M for _ in range(N)]
+    q = deque([])
+    #바이러스 모두 출발 시키기 
+    for i in range(len(virus)):
+        a,b = virus[i]
+        q.append((a,b))
+        visited[a][b] = True
+        whole_visited[a][b] = True
+    while q: 
+        v = q.popleft()
+        for i in range(4):
+            r = v[0]+dx[i]
+            c = v[1]+dy[i]
+            if 0<=r<N and 0<=c<M and not visited[r][c] and maps[r][c]!=1:
+                q.append((r,c))
+                visited[r][c]=True
+                whole_visited[r][c] = True
+
+answer = 0
+
+cases = itertools.permutations(empties,3)
+
+for case in cases:
+    for a,b in case:
+        maps[a][b]=1
+    whole_visited = [[False]*M for _ in range(N)]
+    cnt = 0
+
+    bfs()
+
+    #빈 공간 구하기 
+    for i in range(N):
+        for j in range(M):
+            if not whole_visited[i][j]:
+                cnt+=1
+                
+    answer = max(cnt-wall-3,answer)
+
+    for a,b in case:
+        maps[a][b]=0
+
+print(answer)

syheo/codingTest1/13-17-경쟁적 전염.py

@@ -0,0 +1,48 @@
+#CH13 BFSDFS기출
+#예제 13-17
+#경쟁적 전염
+#백준 18405
+#실버 1
+
+from collections import deque
+
+N , K = map(int,input().split())
+maps = [[(0,0)]*(N+1) for i in range(N+1)] #백신 번호, cnt(초)
+dx = [0,0,1,-1]
+dy = [1,-1,0,0]
+virus = []
+
+
+for i in range(N):
+    tmp = list(map(int,input().split()))
+    maps[i][0]=(0,0)
+    for j in range(N):
+        maps[i+1][j+1]=(tmp[j],0)
+        if tmp[j]>=1:
+            virus.append((i+1,j+1,0)) #virus 좌표, cnt(초)
+
+S,X,Y = map(int,input().split())
+
+def bfs():
+    q = deque(virus)
+    while q:
+        #print(q)
+        row,col,cnt = q.popleft()        
+        if cnt == S:
+            break
+        for i in range(4):
+            r = row + dx[i]
+            c = col + dy[i]
+            if 0<r<=N and 0<c<=N: 
+                #해당 장소에 바이러스가 없으면?
+                if maps[r][c][0] == 0:
+                    maps[r][c]=(maps[row][col][0],cnt+1)
+                    q.append((r,c,cnt+1))
+                #같은 시간대에 먼저 간 바이러슨데 ��가 나보다 우선순위가 낮다면?
+                elif maps[r][c][0] > maps[row][col][0] and maps[r][c][1] == cnt+1:
+                    maps[r][c]=(maps[row][col][0],cnt+1)
+                    q.append((r,c,cnt+1))
+
+bfs()
+print(maps[X][Y][0])
+