[20250825] BOJ / G2 / Escape Room / 한종욱

Author: Ukj0ng

Ukj0ng/202508/25 BOJ G2 Escape Room.md

@@ -0,0 +1,83 @@
+```import java.io.*;
+import java.util.*;
+
+public class Main {
+    private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    private static final BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+    private static List<int[]>[] d;
+    private static int[][] map;
+    private static boolean[][] visited;
+    private static int N, M;
+    public static void main(String[] args) throws IOException {
+        init();
+
+        bw.write(BFS(1, 1) + "\n");
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static void init() throws IOException {
+        N = Integer.parseInt(br.readLine());
+        M = Integer.parseInt(br.readLine());
+
+        map = new int[N+1][M+1];
+        visited = new boolean[N+1][M+1];
+        d = new List[1000001];
+
+        for (int i = 0; i < 1000001; i++) {
+            d[i] = new ArrayList<>();
+        }
+
+        for (int i = 1; i <= N; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            for (int j = 1; j <= M; j++) {
+                map[i][j] = Integer.parseInt(st.nextToken());
+            }
+        }
+    }
+
+    private static String BFS(int x, int y) {
+        Queue<int[]> q = new ArrayDeque<>();
+        visited[x][y] = true;
+        q.add(new int[] {x, y});
+
+        while (!q.isEmpty()) {
+            int[] current = q.poll();
+            if (current[0] == N && current[1] == M) {
+                return "yes";
+            }
+
+            if (d[map[current[0]][current[1]]].size() == 0) {
+                findFactor(map[current[0]][current[1]]);
+            }
+
+            for (int[] element : d[map[current[0]][current[1]]]) {
+                for (int i = 0; i < element.length; i++) {
+                    int nx = element[i];
+                    int ny = element[i^1];
+
+                    if (OOB(nx, ny) || visited[nx][ny]) continue;
+                    visited[nx][ny] = true;
+                    q.add(new int[] {nx, ny});
+                }
+            }
+        }
+
+        return "no";
+    }
+
+    private static void findFactor(int n) {
+        for (int i = 1; i <= Math.sqrt(n); i++) {
+            if (n % i == 0) {
+                d[n].add(new int[] {i, n / i});
+            }
+        }
+    }
+
+    private static boolean OOB(int nx, int ny) {
+        return nx < 1 || nx > N || ny < 1 || ny > M;
+    }
+}
+
+```