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February 28, 2020

The strength of JavaScript is that you can do anything. The weakness is that you will.

- Red Braithwaite

Day 99: Binary Tree Inorder Traversal

Can you write a function to traverse a binary tree in-order, and print out the value of each node as it passes?


The example would output [4, 6, 5] since there is no left child for 4, and 6 is visited in-order before 5.

The definition of a tree node is as follows:

function Node(val) {
  this.val = val;
  this.left = null;
  this.right = null;

Follow up: you'll likely get the recursive solution first, could you do it iteratively?

Have you seen this question before? We are frequently adding problems and may have updated the order. You can change the day that you're on in the settings panel.

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As always, you can see the solution and a full step by step explanation at this link.

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