[20251204] BOJ / P4 / 탈옥 / 한종욱

Ukj0ng/202512/04 BOJ P4 탈옥.md

@@ -0,0 +1,117 @@
+```
+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 int h, w;
+    private static char[][] map;
+    private static int[][][] doors;
+    private static int[][] prisoners;
+
+    public static void main(String[] args) throws IOException {
+        int T = Integer.parseInt(br.readLine());
+
+        while (T-->0) {
+            int answer = 10001;
+
+            init();
+            for (int i = 0; i < 3; i++) {
+                BFS(i);
+            }
+
+            for (int i = 1; i <= h; i++) {
+                for (int j = 1; j <= w; j++) {
+                    if (map[i][j] == '.' || map[i][j] == '$') {
+                        int sum = doors[0][i][j] + doors[1][i][j] + doors[2][i][j];
+                        answer = Math.min(answer, sum);
+                    } else if (map[i][j] == '#') {
+                        int sum = doors[0][i][j] + doors[1][i][j] + doors[2][i][j] - 2;
+                        answer = Math.min(answer, sum);
+                    }
+                }
+            }
+
+            bw.write(answer + "\n");
+        }
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static void init() throws IOException {
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        h = Integer.parseInt(st.nextToken());
+        w = Integer.parseInt(st.nextToken());
+
+        map = new char[h+2][w+2];
+        doors = new int[3][h+2][w+2];
+        prisoners = new int[2][2];
+        int index = 0;
+
+        for (int i = 1; i <= h; i++) {
+            char[] input = br.readLine().toCharArray();
+
+            for (int j = 1; j <= w; j++) {
+                map[i][j] = input[j-1];
+                if (map[i][j] == '$') {
+                    prisoners[index][0] = i;
+                    prisoners[index++][1] = j;
+                }
+            }
+        }
+
+        for (int i = 0; i <= h+1; i++) {
+            map[i][0] = '.';
+            map[i][w+1] = '.';
+        }
+
+        for (int i = 0; i <= w+1; i++) {
+            map[0][i] = '.';
+            map[h+1][i] = '.';
+        }
+    }
+
+    private static void BFS(int index) {
+        Queue<int[]> q = new ArrayDeque<>();
+
+        for (int i = 0; i <= h+1; i++) {
+            Arrays.fill(doors[index][i], 10001);
+        }
+
+        if (index == 2) {
+            doors[index][0][0] = 0;
+            q.add (new int[] {0, 0});
+        }
+        else {
+            doors[index][prisoners[index][0]][prisoners[index][1]] = 0;
+            q.add(new int[] {prisoners[index][0], prisoners[index][1]});
+        }
+
+        while (!q.isEmpty()) {
+            int[] current = q.poll();
+
+            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 (map[nx][ny] == '#' && doors[index][current[0]][current[1]]+1 < doors[index][nx][ny]) {
+                    doors[index][nx][ny] = doors[index][current[0]][current[1]]+1;
+                    q.add(new int[] {nx, ny});
+                } else if ((map[nx][ny] == '.' || map[nx][ny] == '$') && doors[index][current[0]][current[1]] < doors[index][nx][ny]) {
+                    doors[index][nx][ny] = doors[index][current[0]][current[1]];
+                    q.add(new int[] {nx, ny});
+                }
+            }
+        }
+    }
+
+    private static boolean OOB(int nx, int ny) {
+        return nx < 0 || nx > h+1 || ny < 0 || ny > w+1;
+    }
+}
+```