Right Side View of Binary Tree in DSA Javascript - Build from Scratch

Right Side View of Binary Tree

📖 Scenario: Imagine you have a tree of family members, and you want to see only the people who are visible when you look at the tree from the right side.

🎯 Goal: You will build a program that shows the right side view of a binary tree. This means you will list the nodes you see when looking at the tree from the right side, level by level.

📋 What You'll Learn

Create a binary tree using nodes with val, left, and right properties

Use a variable to keep track of the current level while traversing the tree

Write a function to find the right side view of the binary tree

Print the array of node values visible from the right side

💡 Why This Matters

🌍 Real World

Right side view of a binary tree helps in visualizing hierarchical data from a specific perspective, useful in UI trees, organizational charts, and decision trees.

💼 Career

Understanding tree traversal and views is important for software engineers working with data structures, algorithms, and system design.

1

Create the Binary Tree

Create a binary tree with a root node called root. The root node should have val 1, a left child with val 2, and a right child with val 3. The left child of the root should have a right child with val 5, and the right child of the root should have a right child with val 4.

DSA Javascript

// Create the binary tree nodes and link them
// Your code here

Hint

Use objects with val, left, and right properties to build the tree.

2

Set Up Level Tracking Variable

Create a variable called rightView and set it to an empty array. This will store the values of nodes visible from the right side.

DSA Javascript

const root = {
  val: 1,
  left: {
    val: 2,
    left: null,
    right: { val: 5, left: null, right: null }
  },
  right: {
    val: 3,
    left: null,
    right: { val: 4, left: null, right: null }
  }
};

// Create an empty array called rightView
// Your code here

Hint

This array will hold the visible node values from the right side.

3

Write the Right Side View Function

Write a function called rightSideView that takes root as input. Use a helper function called dfs inside it that takes a node and level. Traverse the tree depth-first, and if the current level is equal to the length of rightView, add the node.val to rightView. First visit the right child, then the left child. Call dfs(root, 0) inside rightSideView. Finally, return rightView.

DSA Javascript

const root = {
  val: 1,
  left: {
    val: 2,
    left: null,
    right: { val: 5, left: null, right: null }
  },
  right: {
    val: 3,
    left: null,
    right: { val: 4, left: null, right: null }
  }
};

const rightView = [];

// Write the rightSideView function with dfs helper
// Your code here

Hint

Use depth-first search, visit right child first, then left child, and add node values when first visiting a new level.

4

Print the Right Side View

Call rightSideView(root) and print the result using console.log.

DSA Javascript

const root = {
  val: 1,
  left: {
    val: 2,
    left: null,
    right: { val: 5, left: null, right: null }
  },
  right: {
    val: 3,
    left: null,
    right: { val: 4, left: null, right: null }
  }
};

const rightView = [];

function rightSideView(root) {
  function dfs(node, level) {
    if (!node) return;
    if (level === rightView.length) {
      rightView.push(node.val);
    }
    dfs(node.right, level + 1);
    dfs(node.left, level + 1);
  }
  dfs(root, 0);
  return rightView;
}

// Print the right side view of the tree
// Your code here

Hint

Use console.log(rightSideView(root)) to print the visible nodes.