[20260120] BOJ / G5 / 농장 관리 / 한종욱

Ukj0ng/202601/20 BOJ G5 농장 수열.md

@@ -0,0 +1,87 @@
+```
+import java.io.*;
+import java.util.ArrayDeque;
+import java.util.Queue;
+import java.util.StringTokenizer;
+
+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, 1, 1, -1, -1};
+    private static final int[] dy = {0, 1, 0, -1, 1, -1, 1, -1};
+    private static int[][] arr;
+    private static boolean[][] visited;
+    private static int N, M;
+    private static boolean isPeak;
+
+    public static void main(String[] args) throws IOException {
+        init();
+        int answer = 0;
+
+        for (int i = 0; i < N; i++) {
+            for (int j = 0; j < M; j++) {
+                if (arr[i][j] > 0 && !visited[i][j]) {
+                    isPeak = true; 
+                    BFS(i, j);
+                    if (isPeak) {
+                        answer++;
+                    }
+                }
+            }
+        }
+
+        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());
+
+        arr = new int[N][M];
+        visited = new boolean[N][M];
+
+        for (int i = 0; i < N; i++) {
+            st = new StringTokenizer(br.readLine());
+            for (int j = 0; j < M; j++) {
+                arr[i][j] = Integer.parseInt(st.nextToken());
+            }
+        }
+    }
+
+    private static void BFS(int x, int y) {
+        Queue<int[]> q = new ArrayDeque<>();
+        visited[x][y] = true;
+        q.add(new int[]{x, y});
+
+        while (!q.isEmpty()) {
+            int[] current = q.poll();
+            int cx = current[0];
+            int cy = current[1];
+
+            for (int i = 0; i < 8; i++) {
+                int nx = cx + dx[i];
+                int ny = cy + dy[i];
+
+                if (OOB(nx, ny)) continue;
+
+                if (arr[nx][ny] > arr[cx][cy]) {
+                    isPeak = false;
+                }
+
+                if (arr[nx][ny] == arr[cx][cy] && !visited[nx][ny]) {
+                    visited[nx][ny] = true;
+                    q.add(new int[]{nx, ny});
+                }
+            }
+        }
+    }
+
+    private static boolean OOB(int nx, int ny) {
+        return nx < 0 || nx > N-1 || ny < 0 || ny > M-1;
+    }
+}
+```