Merge pull request #1063 from AlgorithmWithGod/zinnnn37

[20251007] BOJ / G4 / 여행 가자 / 김민진

Author: ShinHeeEul

zinnnn37/202510/7 BOJ G4 여행 가자.md

@@ -0,0 +1,74 @@
+```java
+import java.io.*;
+import java.util.StringTokenizer;
+
+public class BJ_1976_여행_가자 {
+
+	private static final BufferedReader  br = new BufferedReader(new InputStreamReader(System.in));
+	private static final BufferedWriter  bw = new BufferedWriter(new OutputStreamWriter(System.out));
+	private static       StringTokenizer st;
+
+	private static int N, M;
+	private static int[] parents;
+
+	public static void main(String[] args) throws IOException {
+		init();
+		sol();
+
+		bw.flush();
+		bw.close();
+		br.close();
+	}
+
+	private static void init() throws IOException {
+		N = Integer.parseInt(br.readLine());
+		M = Integer.parseInt(br.readLine());
+
+		parents = new int[N + 1];
+		for (int i = 1; i <= N; i++) {
+			parents[i] = i;
+		}
+	}
+
+	private static void sol() throws IOException {
+		for (int i = 1; i <= N; i++) {
+			st = new StringTokenizer(br.readLine());
+			for (int j = 1; j <= N; j++) {
+				if (st.nextToken().equals("0")) continue;
+
+				union(i, j);
+			}
+		}
+
+		st = new StringTokenizer(br.readLine());
+		int v = Integer.parseInt(st.nextToken());
+		while (M-- > 1) {
+			int u = Integer.parseInt(st.nextToken());
+
+			if (find(v) != find(u)) {
+				bw.write("NO\n");
+				return;
+			}
+		}
+		bw.write("YES\n");
+	}
+
+	private static int find(int a) {
+		if (parents[a] == a) return a;
+
+		return parents[a] = find(parents[a]);
+	}
+
+	private static void union(int a, int b) {
+		int rootA = find(a);
+		int rootB = find(b);
+
+		if (rootA < rootB) {
+			parents[rootB] = rootA;
+		} else {
+			parents[rootA] = rootB;
+		}
+	}
+
+}
+```