[20251031] PGM / Lv2 / 전력망을 둘로 나누기 / 이강현

Author: lkhyun

lkhyun/202510/31 PGM Lv2 전력망을 둘로 나누기.md

@@ -0,0 +1,42 @@
+```java
+import java.util.*;
+class Solution {
+    static List<Integer>[] adjList;
+    public int solution(int n, int[][] wires) {
+        int answer = n;
+        adjList = new List[n+1];
+        for(int i = 0; i<=n; i++){
+            adjList[i] = new ArrayList<>();
+        }
+        for(int[] wire : wires){
+            adjList[wire[0]].add(wire[1]);
+            adjList[wire[1]].add(wire[0]);
+        }
+        for(int[] wire : wires){
+            answer = Math.min(answer,Math.abs(n-(2*BFS(n, wire[0],wire[1]))));    
+        }
+        
+        return answer;
+    }
+    public int BFS(int n, int start, int except){
+        int count = 0;
+        ArrayDeque<Integer> q = new ArrayDeque<>();
+        boolean[] visited = new boolean[n+1];
+        q.offer(start);
+        visited[start] = true;
+        count++;
+        
+        while(!q.isEmpty()){
+            int cur = q.poll();
+            
+            for(int next : adjList[cur]){
+                if(visited[next] || next == except) continue;
+                q.offer(next);
+                visited[next] = true;
+                count++;
+            }
+        }
+        return count;
+    }
+}
+```