[20250829] BOJ / G1 / 수영장 만들기 / 이종환

Author: 0224LJH

0224LJH/202508/29 BOJ 수영장 만들기

@@ -0,0 +1,116 @@
+```java
+import java.awt.Point;
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.*;
+
+
+public class Main {
+
+	static boolean[][] visited;
+	static int[][] arr;
+	static int[] dy = {-1,0,1,0};
+	static int[] dx = {0,1,0,-1};
+	
+	static Queue<Point> q = new LinkedList<>();
+	static Queue<Point> temp = new LinkedList<>();
+	
+	static int height,width,ans;
+	static boolean isAvailable;
+	
+
+
+	public static void main(String[] args) throws IOException {
+
+		init();
+		process();
+		print();
+		
+	}
+   
+	public static void init() throws IOException {
+		BufferedReader br = new BufferedReader (new InputStreamReader(System.in));
+		StringTokenizer st = new StringTokenizer(br.readLine());
+		height = Integer.parseInt(st.nextToken());
+		width = Integer.parseInt(st.nextToken());
+		ans = 0;
+		
+		arr = new int[height][width];
+		visited = new boolean[height][width];
+		
+		for (int i = 0 ; i < height; i++) {
+			String[] input = br.readLine().split("");
+			for (int j = 0; j < width; j++) {
+				arr[i][j] = Integer.parseInt(input[j]);
+				System.out.print(arr[i][j]+ " ");
+			}
+			System.out.println();
+		}
+
+	}
+   
+	public static void process() {
+		for (int water = 2; water <= 9; water++) {
+			
+			visited = new boolean[height][width];
+			
+			
+			for (int i = 0; i < height; i++) {
+				for (int j = 0; j < width; j++) {
+					if (visited[i][j]) continue;
+					if (arr[i][j] >= water) continue;
+					
+					isAvailable = true;
+					q.clear();
+					temp.clear();
+					q.add(new Point(j,i));
+					temp.add(new Point(j,i));
+					bfs(water);
+					
+					if (isAvailable) {
+						while(!temp.isEmpty()) {
+							Point p = temp.poll();
+							
+							ans += water - arr[p.y][p.x];
+							arr[p.y][p.x] = water;
+						}
+					}
+					
+				}
+			}
+		}
+
+	}
+	
+	public static void bfs(int water) {
+		while(!q.isEmpty()) {
+			Point p = q.poll();
+			
+			for (int i = 0; i < 4; i++) {
+				int ny = p.y + dy[i];
+				int nx = p.x + dx[i];
+				
+				
+				if (ny < 0 || nx < 0 || ny >= height || nx >= width) {
+					isAvailable = false;
+					continue;
+				}
+				
+				if (visited[ny][nx] || arr[ny][nx] >= water) continue;
+				
+				visited[ny][nx] = true;
+				q.add(new Point(nx,ny));
+				temp.add(new Point(nx,ny));
+			}
+		}
+	}
+
+         
+
+   
+	public static void print() {
+		System.out.println(ans);
+	}
+}
+```