refactor : bfs(미로 탐색)

baekjoon/2178.js

@@ -10,50 +10,42 @@ const [n, m] = input
   .split(" ")
   .map((v) => parseInt(v, 10));
 const map = input.map((v) => v.split("").map((v) => parseInt(v, 10)));
-const visited = map.map((v) => v.map((v) => false));
+const visited = map.map((v) => v.map((v) => 0));
 const dir = [
   [-1, 0],
   [0, 1],
   [1, 0],
   [0, -1],
 ];
-const q1 = new Queue();
-const q2 = new Queue();
-let isFirst = true;
+const q = new Queue();
 let i = 0,
   j = 0;
-let cnt = 1;
 let flag = false;
 
-q1.push([i, j]);
-visited[i][j] = true;
+q.push([i, j]);
+visited[i][j] = 1;
 
-while (!(q1.size === 0 && q2.size === 0)) {
-  while (isFirst ? q1.size !== 0 : q2.size !== 0) {
-    const top = isFirst ? q1.head.value : q2.head.value;
-    isFirst ? q1.pop() : q2.pop();
-    for (let i = 0; i < 4; i++) {
-      const next = [top[0] + dir[i][0], top[1] + dir[i][1]];
-      if (
-        next[0] < 0 ||
-        next[0] >= n ||
-        next[1] < 0 ||
-        next[1] >= m ||
-        map[next[0]][next[1]] === 0 ||
-        visited[next[0]][next[1]] === true
-      )
-        continue;
-      isFirst ? q2.push(next) : q1.push(next);
-      visited[next[0]][next[1]] = true;
-      if (next[0] === n - 1 && next[1] === m - 1) {
-        flag = true;
-        break;
-      }
+while (q.size !== 0) {
+  const top = q.head.value;
+  q.pop();
+  for (let i = 0; i < 4; i++) {
+    const next = [top[0] + dir[i][0], top[1] + dir[i][1]];
+    if (
+      next[0] < 0 ||
+      next[0] >= n ||
+      next[1] < 0 ||
+      next[1] >= m ||
+      map[next[0]][next[1]] === 0 ||
+      visited[next[0]][next[1]] > 0
+    )
+      continue;
+    q.push(next);
+    visited[next[0]][next[1]] = visited[top[0]][top[1]] + 1;
+    if (next[0] === n - 1 && next[1] === m - 1) {
+      flag = true;
+      break;
     }
   }
-  cnt++;
-  isFirst = !isFirst;
-  if (flag) break;
 }
 
-console.log(cnt);
+console.log(visited[n - 1][m - 1]);