Merge pull request #52 from AlgoLeadMe/15-mong3125

15-mong3125

mong3125/그래프/BOJ7569_토마토.java

@@ -0,0 +1,84 @@
+package 그래프;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.*;
+
+public class BOJ7569_토마토 {
+
+    static int M, N, H;
+    static int[][][] box;
+
+    static Queue<int[]> ripen = new LinkedList<>();   // 익은 토마토 위치
+    static int notRipenTomatos = 0;
+    static int result = 1;
+    static int[][] directions = {
+            {1, 0, 0},
+            {-1, 0, 0},
+            {0, 1, 0},
+            {0, -1, 0},
+            {0, 0, 1},
+            {0, 0, -1},
+    };
+
+    public static void main(String[] args) throws IOException {
+        // == 입력 == //
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+
+        M = Integer.parseInt(st.nextToken());
+        N = Integer.parseInt(st.nextToken());
+        H = Integer.parseInt(st.nextToken());
+        box = new int[H][N][M];
+
+        for (int i = 0; i < H; i++) {
+            for (int j = 0; j < N; j++) {
+                st = new StringTokenizer(br.readLine());
+                for (int k = 0; k < M; k++) {
+                    box[i][j][k] = Integer.parseInt(st.nextToken());
+
+                    // 익은 토마토 위치 저장
+                    if (box[i][j][k] == 1) ripen.add(new int[]{i, j, k});
+                    else if (box[i][j][k] == 0) notRipenTomatos++;
+                }
+            }
+        }
+
+        // == 풀이 == //
+        bfs();
+
+        // 모든 토마토가 익은게 아니라면 -1 반환
+        if (notRipenTomatos > 0) {
+            result = 0;
+        }
+
+        // == 출력 == //
+        System.out.println(result - 1);
+    }
+
+    public static void bfs() {
+        while (!ripen.isEmpty()) {
+            int[] tomato = ripen.remove();
+            for (int[] direction : directions) {
+                int z = tomato[0] + direction[0];
+                int y = tomato[1] + direction[1];
+                int x = tomato[2] + direction[2];
+
+                if (isInRange(z, y, x)) {
+                    if (box[z][y][x] == 0) {
+                        box[z][y][x] = box[tomato[0]][tomato[1]][tomato[2]] + 1;
+                        result = Math.max(result, box[z][y][x]);
+                        notRipenTomatos--;
+
+                        ripen.add(new int[]{z, y, x});
+                    }
+                }
+            }
+        }
+    }
+
+    public static boolean isInRange(int z, int y, int x) {
+        return (x >= 0 && x < M && y >= 0 && y < N && z >= 0 && z < H);
+    }
+}