Create 2764-is-array-a-preorder-of-some-binary-tree.js

Author: everthis

2764-is-array-a-preorder-of-some-binary-tree.js

@@ -0,0 +1,19 @@
+/**
+ * @param {number[][]} nodes
+ * @return {boolean}
+ */
+var isPreorder = function(nodes) {
+  const stack = [];
+
+  for (const [curr, parent] of nodes) {
+    while (stack.length && stack[stack.length - 1] !== parent) {
+      stack.pop();
+    }
+    if (!stack.length && parent !== -1) {
+      return false;
+    }
+    stack.push(curr);
+  }
+
+  return true;
+};