21736 헌내기는 친구가 필요해

Author: memory-h

src/main/java/bfs/silver/silver_2/_21736.java

@@ -0,0 +1,79 @@
+package bfs.silver.silver_2;
+
+import java.io.*;
+import java.util.LinkedList;
+import java.util.Queue;
+import java.util.StringTokenizer;
+
+public class _21736 {
+
+    private static int n;
+    private static int m;
+
+    private static char[][] graph;
+    private static boolean[][] visited;
+    private static Queue<int[]> queue;
+
+    private static int[] dx = {-1, 1, 0, 0};
+    private static int[] dy = {0, 0, -1, 1};
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        StringBuilder sb = new StringBuilder();
+
+        n = Integer.parseInt(st.nextToken());
+        m = Integer.parseInt(st.nextToken());
+
+        graph = new char[n][m];
+        visited = new boolean[n][m];
+        queue = new LinkedList<>();
+
+        for (int i = 0; i < n; i++) {
+            String input = br.readLine();
+
+            for (int j = 0; j < m; j++) {
+                graph[i][j] = input.charAt(j);
+
+                if (graph[i][j] == 'I') {
+                    queue.offer(new int[]{i, j});
+                }
+            }
+        }
+
+        bw.write(bfs());
+        bw.flush();
+        bw.close();
+    }
+
+    private static String bfs() {
+        int count = 0;
+
+        while (!queue.isEmpty()) {
+            int[] cur = queue.poll();
+
+            for (int i = 0; i < 4; i++) {
+                int nx = cur[0] + dx[i];
+                int ny = cur[1] + dy[i];
+
+                if (nx < 0 || ny < 0 || nx >= n || ny >= m || graph[nx][ny] == 'X') {
+                    continue;
+                }
+
+                if (!visited[nx][ny]) {
+                    visited[nx][ny] = true;
+
+                    if (graph[nx][ny] == 'P') {
+                        count++;
+                    }
+
+                    queue.offer(new int[]{nx, ny});
+                }
+            }
+        }
+
+        return count == 0 ? "TT" : String.valueOf(count);
+    }
+
+}