[BFS] baekjoon-7576

Author: Seogeurim

README.md

@@ -40,6 +40,7 @@
 | 05  |     | [Baekjoon-16236 아기 상어](./src/BFS/P16236) |   삼성 SW 역량 테스트 기출   |
 | 06  |     | [Baekjoon-14502 연구소](./src/BFS/P14502) |   삼성 SW 역량 테스트 기출   |
 | 07  |     | [Baekjoon-1525 퍼즐](./src/BFS/P1525) |      |
+| 08  |     | [Baekjoon-7576 토마토](./src/BFS/P7576) |      |
 
 ## Simulation
 

src/BFS/P7576/Main.java

@@ -0,0 +1,92 @@
+package BFS.P7576;
+
+import java.io.BufferedReader;
+import java.io.FileInputStream;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.Queue;
+import java.util.StringTokenizer;
+
+public class Main {
+
+    static int M, N;
+    static int[][] box;
+
+    static int[] di = {-1, 0, 1, 0};
+    static int[] dj = {0, 1, 0, -1};
+
+    static Queue<Position> q = new LinkedList<>();
+    static int ans = -1;
+
+    public static void main(String[] args) throws Exception {
+        System.setIn(new FileInputStream("src/BFS/P7576/input.txt"));
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+
+        M = Integer.parseInt(st.nextToken());
+        N = Integer.parseInt(st.nextToken());
+
+        box = new int[N][M];
+        for (int i = 0; i < N; i++) {
+            st = new StringTokenizer(br.readLine());
+            for (int j = 0; j < M; j++) {
+                box[i][j] = Integer.parseInt(st.nextToken());
+                if (box[i][j] == 1) q.offer(new Position(i, j));
+            }
+        }
+
+        while (!q.isEmpty()) {
+            ans ++;
+            if (checkDone()) break;
+
+            int curSize = q.size();
+            for (int i = 0; i < curSize; i++) {
+                Position cur = q.poll();
+                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) && box[to_i][to_j] == 0) {
+                        box[to_i][to_j] = 1;
+                        q.offer(new Position(to_i, to_j));
+                    }
+                }
+            }
+        }
+
+        if (!checkDone()) System.out.println(-1);
+        else System.out.println(ans);
+    }
+
+    static boolean isValidPath(int i, int j) {
+        return 0 <= i && i < N && 0 <= j && j < M;
+    }
+
+    static boolean checkDone() {
+        for (int i = 0; i < N; i++) {
+            for (int j = 0; j < M; j++) {
+                if (box[i][j] == 0) return false;
+            }
+        }
+        return true;
+    }
+}
+
+class Position {
+    int i;
+    int j;
+
+    public Position(int i, int j) {
+        this.i = i;
+        this.j = j;
+    }
+
+    @Override
+    public String toString() {
+        return "Position{" +
+                "i=" + i +
+                ", j=" + j +
+                '}';
+    }
+}

src/BFS/P7576/README.md

@@ -0,0 +1,4 @@
+## [baekjoon-7576] 토마토
+
+![image](https://user-images.githubusercontent.com/22045163/96839353-052ce900-1484-11eb-845f-d76c0d11a9a3.png)
+

src/BFS/P7576/input.txt

@@ -0,0 +1,6 @@
+5 5
+-1 1 0 0 0
+0 -1 -1 -1 0
+0 -1 -1 -1 0
+0 -1 -1 -1 0
+0 0 0 0 0