[20251113] BOJ / G1 / 달이 차오른다, 가자 / 이준희

JHLEE325/202511/13 BOJ G1 달이 차오른다, 가자.md

@@ -0,0 +1,87 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+    static int N, M;
+    static char[][] map;
+    static boolean[][][] visited;
+    static int[] dy = {-1, 1, 0, 0};
+    static int[] dx = {0, 0, -1, 1};
+
+    static class State {
+        int y, x, keybit, dist;
+        State(int y, int x, int keybit, int dist) {
+            this.y = y;
+            this.x = x;
+            this.keybit = keybit;
+            this.dist = dist;
+        }
+    }
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        N = Integer.parseInt(st.nextToken());
+        M = Integer.parseInt(st.nextToken());
+
+        map = new char[N][M];
+        visited = new boolean[1<<6][N][M];
+        int starty = 0;
+        int startx = 0;
+
+        for (int i = 0; i < N; i++) {
+            String line = br.readLine();
+            for (int j = 0; j < M; j++) {
+                map[i][j] = line.charAt(j);
+                if (map[i][j] == '0') {
+                    starty = i; startx = j;
+                    map[i][j] = '.';
+                }
+            }
+        }
+
+        int ans = bfs(starty, startx);
+        System.out.println(ans);
+    }
+
+    static int bfs(int y, int x) {
+        Queue<State> q = new LinkedList<>();
+        q.offer(new State(y, x, 0, 0));
+        visited[0][y][x] = true;
+
+        while (!q.isEmpty()) {
+            State cur = q.poll();
+            if (map[cur.y][cur.x] == '1') {
+                return cur.dist;
+            }
+
+            for (int d = 0; d < 4; d++) {
+                int ny = cur.y + dy[d];
+                int nx = cur.x + dx[d];
+                int nKey = cur.keybit;
+
+                if (ny < 0 || nx < 0 || ny >= N || nx >= M) continue;
+                char ch = map[ny][nx];
+
+                if (ch == '#') continue;
+
+                if (ch >= 'A' && ch <= 'F') {
+                    int needed = 1 << (ch - 'A');
+                    if ((nKey & needed) == 0) continue;
+                }
+                if (ch >= 'a' && ch <= 'f') {
+                    nKey = nKey | (1 << (ch - 'a'));
+                }
+
+                if (!visited[nKey][ny][nx]) {
+                    visited[nKey][ny][nx] = true;
+                    q.offer(new State(ny, nx, nKey, cur.dist + 1));
+                }
+            }
+        }
+
+        return -1;
+    }
+}
+```