10.05 : bfs(토마토)

baekjoon/7576.js

@@ -0,0 +1,52 @@
+// 토마토 : 그래프 탐색, 너비 우선 탐색
+const Queue = require("./queue");
+const map = require("fs")
+  .readFileSync("/dev/stdin")
+  .toString()
+  .trim()
+  .split("\n")
+  .map((v) => v.split(" ").map((v) => parseInt(v, 10)));
+const [m, n] = map.shift();
+const q = new Queue();
+const dir = [
+  [-1, 0],
+  [0, 1],
+  [1, 0],
+  [0, -1],
+];
+let cnt = 0;
+let flag = false;
+let answer = 1;
+
+for (let i = 0; i < n; i++)
+  for (let j = 0; j < m; j++) {
+    if (map[i][j] === 1) q.push([i, j]);
+    else if (map[i][j] === 0) cnt++;
+  }
+
+while (q.size !== 0) {
+  const top = q.head.value;
+  q.pop();
+  for (let i = 0; i < dir.length; i++) {
+    const next = [top[0] + dir[i][0], top[1] + dir[i][1]];
+    if (
+      next[0] >= n ||
+      next[0] < 0 ||
+      next[1] >= m ||
+      next[1] < 0 ||
+      map[next[0]][next[1]] !== 0
+    )
+      continue;
+    map[next[0]][next[1]] = map[top[0]][top[1]] + 1;
+    answer = Math.max(map[next[0]][next[1]], answer);
+    cnt--;
+    if (cnt === 0) {
+      flag = true;
+      break;
+    }
+    q.push(next);
+  }
+  if (flag) break;
+}
+
+console.log(cnt ? -1 : answer - 1);