[20251024] BOJ / G2 / 아맞다우산 / 한종욱

Ukj0ng/202510/24 BOJ G2 아맞다우산.md

@@ -0,0 +1,99 @@
+```
+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 final int[] dx = {1, 0, -1, 0};
+    private static final int[] dy = {0, 1, 0, -1};
+    private static char[][] map;
+    private static boolean[][][] visited;
+    private static int[] start, end;
+    private static int N, M, count;
+    public static void main(String[] args) throws IOException {
+        init();
+        int answer = BFS();
+
+        bw.write(answer + "\n");
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static void init() throws IOException {
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        N = Integer.parseInt(st.nextToken());
+        M = Integer.parseInt(st.nextToken());
+
+        map = new char[M][N];
+        start = new int[2];
+        end = new int[2];
+
+        for (int i = 0; i < M; i++) {
+            map[i] = br.readLine().toCharArray();
+            for (int j = 0; j < N; j++) {
+                if (map[i][j] == 'S') {
+                    start[0] = i;
+                    start[1] = j;
+                } else if (map[i][j] == 'E') {
+                    end[0] = i;
+                    end[1] = j;
+                } else if (map[i][j] == 'X') {
+                    map[i][j] = (char) (count + '0');
+                    count++;
+                }
+            }
+        }
+
+        visited = new boolean[M][N][1 << count];
+    }
+
+    private static int BFS() {
+        Queue<int[]> q = new ArrayDeque<>();
+        int result = 0;
+        visited[start[0]][start[1]][0] = true;
+        q.add(new int[]{start[0], start[1], 0, 0});
+
+        while (!q.isEmpty()) {
+            int[] current = q.poll();
+
+            if (current[0] == end[0] && current[1] == end[1] && current[2] == (1 << count)-1) {
+                result = current[3];
+                break;
+            }
+
+            for (int i = 0; i < 4; i++) {
+                int nx = current[0] + dx[i];
+                int ny = current[1] + dy[i];
+
+                if (OOB(nx, ny) || map[nx][ny] == '#') continue;
+
+                if (!isThings(nx, ny) && !visited[nx][ny][current[2]]) {
+                    visited[nx][ny][current[2]] = true;
+                    q.add(new int[]{nx, ny, current[2], current[3]+1});
+                } else if (isThings(nx, ny)) {
+                    int v = 1 << (map[nx][ny] - '0');
+                    if (visited[nx][ny][current[2] | v]) continue;
+                    visited[nx][ny][current[2] | v] = true;
+                    q.add(new int[]{nx, ny, current[2] | v, current[3] + 1});
+                }
+
+            }
+        }
+
+        return result;
+    }
+
+    private static boolean OOB(int nx, int ny) {
+        return nx < 0 || nx > M-1 || ny < 0 || ny > N-1;
+    }
+
+    private static boolean isThings(int nx, int ny) {
+        return map[nx][ny] != '#' &&
+                map[nx][ny] != 'S' &&
+                map[nx][ny] != 'E' &&
+                map[nx][ny] != '.';
+    }
+}
+```