Compare Claude Opus 4.1 by Anthropic against Qwen3 Coder Next by Qwen, context windows of 200K vs 262K, tested across 25 shared challenges. Updated February 2026.
25 challenges
Tests an AI's ability to solve a simple but potentially confusing logic puzzle
Let me work through this step-by-step.
Sally has 3 brothers.
Each of Sally's brothers has 2 sisters.
Since Sally is a girl, she is one of the sisters that each brother has.
If each brother has 2 sisters total, and Sally is one of them, then there must be 1 other sister besides Sally.
Therefore, Sally has 1 sister.
Let's break it down carefully.
Now, consider the statement: "Each brother has 2 sisters."
Who are the sisters of Sally’s brothers?
The brothers share the same siblings — the same family. So Sally and her sisters are the sisters of each brother.
We know Sally is one sister. Let the number of other sisters (besides Sally) be $ x $. So total sisters = $ 1 + x $.
Each brother has 2 sisters, so:
$$ 1 + x = 2 \Rightarrow x = 1 $$
So there is 1 other sister besides Sally.
Therefore, Sally has 1 sister (besides herself), meaning 2 sisters total — but wait — when we say "how many sisters does Sally have?", we don’t count herself. So:
✅ Let’s verify:
Yes, consistent.
Answer: Sally has 1 sister.
Tests an AI's randomness and creativity
Tests an AI's ability to create detailed SVG illustrations of gaming hardware
Tests an AI's ability to simulate personalities and predict future trends
Tests an AI's humor and understanding of current events
Tests an AI's ability to generate a complete, working landing page
Recreate an interactive, classic Mario level in a single HTML file.
Tests an AI's UI design skills with theming support
Tests an AI's ability to engage in philosophical discourse about AI rights
Generate SVG art of a randomly chosen animal in a setting of its choosing.
Generate a unique and simple recipe with common ingredients.
Create a starter plan for improving long-term health.
