Merge pull request #1213 from AlgorithmWithGod/JHLEE325

[20251024] BOJ / G1 / 수영장 만들기 / 이준희

Author: ShinHeeEul

JHLEE325/202510/24 BOJ G1 수영장 만들기.md

@@ -0,0 +1,76 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    static int n, m, res;
+    static int[][] map;
+    static boolean[][] visited;
+    static int[] dx = {-1, 1, 0, 0};
+    static int[] dy = {0, 0, -1, 1};
+
+    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 int[n + 2][m + 2];
+
+        for (int i = 1; i <= n; i++) {
+            String s = br.readLine();
+            for (int j = 1; j <= m; j++) {
+                map[i][j] = Integer.parseInt(String.valueOf(s.charAt(j-1)));
+            }
+        }
+
+        for (int k = 2; k <= 9; k++) {
+            visited = new boolean[n + 2][m + 2];
+            for (int i = 1; i <= n; i++) {
+                for (int j = 1; j <= m; j++) {
+                    if(visited[i][j]||map[i][j]>=k)
+                        continue;
+                    res += bfs(i, j, k);
+                }
+            }
+        }
+        System.out.println(res);
+    }
+
+    static int bfs(int x, int y, int height) {
+        Queue<int[]> q = new ArrayDeque<>();
+        List<int[]> list = new ArrayList<>();
+        boolean ground = false;
+        int water = 0;
+        q.add(new int[]{x, y});
+        list.add(new int[]{x, y});
+
+        while (!q.isEmpty()) {
+            int[] cur = q.poll();
+            for (int d = 0; d < 4; d++) {
+                int nx = cur[0] + dx[d];
+                int ny = cur[1] + dy[d];
+                if (map[nx][ny] == 0) {
+                    ground=true;
+                    continue;
+                }
+                if (!visited[nx][ny] && map[nx][ny] < height) {
+                    q.add(new int[]{nx, ny});
+                    list.add(new int[]{nx, ny});
+                    visited[nx][ny] = true;
+                }
+            }
+        }
+        if(ground)
+            return 0;
+
+        for (int[] pool : list) {
+            water += height - map[pool[0]][pool[1]];
+            map[pool[0]][pool[1]] = height;
+        }
+        return water;
+    }
+}
+```