Elements in First Not Second
Computes set difference A - B, highlighting unique elements in array A.
Live loop — open the studio to scrub, add your own array, or race it in Battle Arena.
Asked in interviews at
Reference implementation (Python)
def difference_a_minus_b(a, b):
set_b = set(b)
return [x for x in a if x not in set_b]Embed this visualization
Drop a live, looping Elements in First Not Second canvas into a blog post or course page.
<iframe src="/embed/elements-in-first-not-second" width="100%" height="380" style="border:1px solid #e6e8ec;border-radius:14px" loading="lazy" title="3D algorithm visualization by CodeWithMunnaX"></iframe>Frequently asked
What is the time and space complexity of Elements in First Not Second?
Elements in First Not Second runs in O(n) time and O(n) auxiliary space.
Is the Elements in First Not Second visualizer free?
The core 3D visualizer, Web Audio chimes and step intuition are free. A one-time ₹49 Pro Pass unlocks advanced algorithms, large custom arrays, Battle Arena and reel export.
Which companies ask Elements in First Not Second in interviews?
Elements in First Not Second shows up in interviews at Goldman Sachs, Adobe, Salesforce.
How does the 3D visualization of Elements in First Not Second work?
Each array value becomes a 3D pillar whose height maps to its value. Comparisons glow amber, swaps flash red, and settled elements lock green while a floating pointer badge tracks the active index — synchronized line-by-line with the Python code.