From 3e594b056bfbd664c041406b02a18e8f607b7bbe Mon Sep 17 00:00:00 2001
From: LiiNi-coder <97495437+LiiNi-coder@users.noreply.github.com>
Date: Mon, 29 Dec 2025 15:08:57 +0900
Subject: [PATCH] =?UTF-8?q?[20251229]=20BOJ=20/=20G3=20/=20=EC=8A=A4?=
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---
 ...\354\247\200 \353\257\274\355\230\2702.md" | 67 +++++++++++++++++++
 1 file changed, 67 insertions(+)
 create mode 100644 "LiiNi-coder/202512/29 BOJ \354\212\244\355\201\254\353\243\250\354\247\200 \353\257\274\355\230\2702.md"

diff --git "a/LiiNi-coder/202512/29 BOJ \354\212\244\355\201\254\353\243\250\354\247\200 \353\257\274\355\230\2702.md" "b/LiiNi-coder/202512/29 BOJ \354\212\244\355\201\254\353\243\250\354\247\200 \353\257\274\355\230\2702.md"
new file mode 100644
index 00000000..55e1d2f9
--- /dev/null
+++ "b/LiiNi-coder/202512/29 BOJ \354\212\244\355\201\254\353\243\250\354\247\200 \353\257\274\355\230\2702.md"	
@@ -0,0 +1,67 @@
+```java
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.List;
+
+public class Main{
+	private static List<List<Integer>> Graph;
+	private static int N;
+	private static int[][] Dp;
+	private static boolean[] Visited;
+	public static void main(String args[]) throws IOException {
+		/*
+		* dfs(2, parent=none)
+		* dfs(1, parent=2)
+		* dfs(4, parent=2)
+		* dfs(3, parent-2)
+		*
+		* dfs(1, parent=2)
+		* */
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		N = Integer.parseInt(br.readLine());
+		Dp = new int[N+1][2];
+		// [v][0]: 노드v를 루트으로 하는 부분트리(노드v엔 경찰서없음)에서 최소 경찰서개수
+		// [v][1]: 노드v를 루트로 하는 부부늩리(노드v엔 경찰서있음)에서 최소 경찰서 개수
+		String[] temp;
+		Visited = new boolean[N+1];
+		Graph = new ArrayList<List<Integer>>();
+		for(int i = 0; i < N+1; i++)
+			Graph.add(new ArrayList<Integer>());
+		for(int i = 0; i < N-1; i++){
+			temp = br.readLine().split(" ");
+			int a = Integer.parseInt(temp[0]);
+			int b = Integer.parseInt(temp[1]);
+			Graph.get(a).add(b);
+			Graph.get(b).add(a);
+		}
+		//dfs
+		for(int i = 1; i<N+1; i++)
+			dfs(i, 0);
+		int answer = 0;
+		for(int i = 1; i<N+1; i++){
+			answer = Math.max(answer, Math.min(Dp[i][0], Dp[i][1]));
+		}
+		System.out.println(answer);
+		br.close();
+	}
+	private static void dfs(int cur, int parent){
+		if(Visited[cur]) return;
+		Dp[cur][0] = 0;
+		Dp[cur][1] = 1;
+		for(int next: Graph.get(cur)){
+			if(next == parent) continue;
+			dfs(next, cur);
+		}
+		for(int next: Graph.get(cur)){
+			if(next == parent) continue;
+			//cur노드에 경찰서-> 자식엔 경찰서가 있어도 없어도됨
+			Dp[cur][1] += Math.min(Dp[next][0], Dp[next][1]);
+			//cur노드에 경찰서 두지않음 -> 자식엔 경찰서가 반드시 있어야함
+			Dp[cur][0] += Dp[next][1];
+		}
+		Visited[cur] = true;
+	}
+}
+```