Merge pull request #506 from AlgorithmWithGod/JHLEE325

[20250720] BOJ / G4 / 여행가자 / 이준희

Author: ShinHeeEul

JHLEE325/202507/20 BOJ G4 여행가자.md

@@ -0,0 +1,56 @@
+```java
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.util.*;
+
+public class Main {
+
+    public static void main(String[] args) throws Exception {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st;
+
+        int n = Integer.parseInt(br.readLine());
+        int m = Integer.parseInt(br.readLine());
+
+        int[][] map = new int[n][n];
+
+        for (int i = 0; i < n; i++) {
+            st = new StringTokenizer(br.readLine());
+            for (int j = 0; j < n; j++) {
+                map[i][j] = Integer.parseInt(st.nextToken());
+                if (i == j) {
+                    map[i][j] = 1;
+                }
+            }
+        }
+
+        for (int k = 0; k < n; k++) {
+            for (int i = 0; i < n; i++) {
+                for (int j = 0; j < n; j++) {
+                    if (map[i][k] == 1 && map[k][j] == 1)
+                        map[i][j] = 1;
+                }
+            }
+        }
+
+        int[] route = new int[m];
+        st = new StringTokenizer(br.readLine());
+        for (int i = 0; i < m; i++) {
+            route[i] = Integer.parseInt(st.nextToken());
+        }
+
+        if (m == 1) {
+            System.out.println("YES");
+            return;
+        }
+
+        for (int i = 0; i < m - 1; i++) {
+            if (map[route[i] - 1][route[i + 1] - 1] == 0) {
+                System.out.println("NO");
+                return;
+            }
+        }
+        System.out.println("YES");
+    }
+}
+```