[20251109] BOJ / P5 / 집배원 한상덕 / 한종욱

Ukj0ng/202511/09 BOJ P5 집배원 한상덕.md

@@ -0,0 +1,106 @@
+```
+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, -1, -1, 0, 0, 1, 1, 1};
+    private static final int[] dy = {-1, 0, 1, -1, 1, -1, 0, 1};
+    private static List<Integer> list;
+    private static char[][] map;
+    private static boolean[][] visited;
+    private static int[][] height;
+    private static int[] start;
+    private static int N, K;
+    public static void main(String[] args) throws IOException {
+        init();
+        int answer = twoPointer();
+
+        bw.write(answer + "\n");
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static void init() throws IOException {
+        N = Integer.parseInt(br.readLine());
+
+        map = new char[N][N];
+        height = new int[N][N];
+        visited = new boolean[N][N];
+        start = new int[2];
+
+        for (int i = 0; i < N; i++) {
+            map[i] = br.readLine().toCharArray();
+            for (int j = 0; j < N; j++) {
+                if (map[i][j] == 'P') {
+                    start[0] = i;
+                    start[1] = j;
+                }
+                if (map[i][j] == 'K') K++;
+            }
+        }
+
+        Set<Integer> set = new TreeSet<>();
+        for (int i = 0; i < N; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            for (int j = 0; j < N; j++) {
+                height[i][j] = Integer.parseInt(st.nextToken());
+                set.add(height[i][j]);
+            }
+        }
+
+        list = new ArrayList<>(set);
+    }
+
+    private static int twoPointer() {
+        int result = Integer.MAX_VALUE;
+        int left = 0;
+
+        for (int right = 0; right < list.size(); right++) {
+            while (left <= right) {
+                if (valid(list.get(left), list.get(right))) {
+                    result = Math.min(result, list.get(right) - list.get(left));
+                    left++;
+                } else break;
+            }
+        }
+
+        return result;
+    }
+
+    private static boolean valid(int min, int max) {
+        if (height[start[0]][start[1]] < min || height[start[0]][start[1]] > max) return false;
+
+        Queue<int[]> q = new ArrayDeque<>();
+        for (int i = 0; i < N; i++) Arrays.fill(visited[i], false);
+        visited[start[0]][start[1]] = true;
+        q.add(new int[]{start[0], start[1]});
+
+        int temp = 0;
+
+        while (!q.isEmpty()) {
+            int[] current = q.poll();
+
+            if (map[current[0]][current[1]] == 'K') temp++;
+
+            for (int i = 0; i < 8; i++) {
+                int nx = current[0] + dx[i];
+                int ny = current[1] + dy[i];
+
+                if (OOB(nx, ny) || visited[nx][ny] || height[nx][ny] < min || height[nx][ny] > max) continue;
+
+                visited[nx][ny] = true;
+                q.add(new int[]{nx, ny});
+            }
+        }
+
+        return temp == K;
+    }
+
+    private static boolean OOB(int nx, int ny) {
+        return nx < 0 || nx > N-1 || ny < 0 || ny > N-1;
+    }
+}
+```