ALGODAILY

January 22, 2020

If Java had true garbage collection, most programs would delete themselves upon execution.

- Robert Sewell

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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?

  4
   \
    5
   /
  6

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?

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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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