[DFS] baekjoon-2667

Author: Seogeurim

README.md

@@ -26,6 +26,7 @@
 | 07  |     | [Baekjoon-14501 퇴사](./src/DFS/P14501) |      |
 | 08  |     | [Baekjoon-10971 외판원 순회 2](./src/DFS/P10971) |      |
 | 09  |     | [Baekjoon-14500 테트로미노](./src/DFS/P14500) |      |
+| 10  |     | [Baekjoon-2667 단지번호붙이기](./src/DFS/P2667) |      |
 
 ### BFS
 

src/DFS/P2667/Main.java

@@ -0,0 +1,70 @@
+package DFS.P2667;
+
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    static int N;
+    static int[][] board;
+    static boolean[][] visited;
+
+    static int[] di = {-1, 0, 1, 0};
+    static int[] dj = {0, 1, 0, -1};
+
+    static ArrayList<Integer> list = new ArrayList<>();
+    static int count = 0;
+
+    public static void main(String[] args) throws Exception {
+        System.setIn(new FileInputStream("src/DFS/P2667/input.txt"));
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+        N = Integer.parseInt(br.readLine());
+        board = new int[N][N];
+        visited = new boolean[N][N];
+
+        for (int i = 0; i < N; i++) {
+            String line = br.readLine();
+            for (int j = 0; j < N; j++) {
+                board[i][j] = line.charAt(j) - '0';
+            }
+        }
+
+        for (int i = 0; i < N; i++) {
+            for (int j = 0; j < N; j++) {
+                if (!visited[i][j]) {
+                    dfs(i, j);
+                    if (count > 0) {
+                        list.add(count);
+                        count = 0;
+                    }
+                }
+            }
+        }
+
+        Collections.sort(list);
+        System.out.println(list.size());
+        for (int item: list) System.out.println(item);
+    }
+
+    static void dfs(int cur_i, int cur_j) {
+        visited[cur_i][cur_j] = true;
+
+        if (board[cur_i][cur_j] == 1) {
+            count ++;
+
+            for (int t = 0; t < 4; t++) {
+                int to_i = cur_i + di[t];
+                int to_j = cur_j + dj[t];
+
+                if (isValidPath(to_i, to_j) && !visited[to_i][to_j]) {
+                    dfs(to_i, to_j);
+                }
+            }
+        }
+    }
+
+    static boolean isValidPath(int i, int j) {
+        return 0 <= i && i < N && 0 <= j && j < N;
+    }
+}

src/DFS/P2667/README.md

@@ -0,0 +1,3 @@
+## [baekjoon-2667] 단지번호붙이기
+
+![image](https://user-images.githubusercontent.com/22045163/96833690-d1e65c00-147b-11eb-96dc-e0d257eac3ef.png)

src/DFS/P2667/input.txt

@@ -0,0 +1,8 @@
+7
+0110100
+0110101
+1110101
+0000111
+0100000
+0111110
+0111000