Create 1466.重新规划路线.js

Author: yinxin630

1466.重新规划路线.js

@@ -0,0 +1,33 @@
+/**
+ * @param {number} n
+ * @param {number[][]} connections
+ * @return {number}
+ */
+var minReorder = function(n, connections) {
+    const map = new Map();
+    for (const [a, b] of connections) {
+        const map1 = map.get(a) || new Map();
+        map1.set(b, 1);
+        map.set(a, map1);
+        const map2 = map.get(b) || new Map();
+        map2.set(a, 0);
+        map.set(b, map2);
+    }
+
+    const queue = [0];
+    let arrive = new Set(queue);
+    let result = 0;
+    while (queue.length) {
+        const i = queue.shift();
+        const next = map.get(i);
+        for (const n of next.keys()) {
+            if (arrive.has(n)) {
+                continue;
+            }
+            result += next.get(n);
+            queue.push(n);
+            arrive.add(n);
+        }
+    }
+    return result;
+};