2024-05-30

mjj111/graph/양과늑대.java

@@ -0,0 +1,39 @@
+import java.util.*;
+
+class 양과늑대 {
+
+    int[][] edges;
+    int[] info;
+    int maxSheepCnt = 0;
+
+    public int solution(int[] Info, int[][] Edges) {
+        info = Info;
+        edges = Edges;
+        dfs(0, 0, 0, new HashSet<Integer>());
+        return maxSheepCnt;
+    }
+
+    private void dfs(int now, int sheepCnt, int wolfCnt, Set<Integer> nexts) {
+        if (info[now] == 0) sheepCnt++;
+        else wolfCnt++;
+
+        if (wolfCnt >= sheepCnt) return;
+        maxSheepCnt = Math.max(sheepCnt, maxSheepCnt);
+
+        // 다음 탐색 위치 복사
+        Set<Integer> copySet = new HashSet<>(nexts);
+
+        // 다음 탐색 목록중 현재 위치제외
+        copySet.remove(now);
+
+        for(int[] edge : edges) {
+            int start = edge[0];
+            int end = edge[1];
+            if(start == now) copySet.add(end);
+        }
+
+        for (int next : copySet) {
+            dfs(next, sheepCnt, wolfCnt, copySet);
+        }
+    }
+}