C# support, deeper study groups, and better verdicts

C# is here

C# joins Python, JavaScript, Java, C++, Go, and Rust as a fully supported language, with starting templates on every problem.

Study groups grew up

• Hosts can now pick the problem or topic for a session instead of getting a random one.
• Past-session history: see what your group has solved before.
• Group solution viewing: after a session, browse how everyone in the group solved it.

See any submission properly

Submissions now open in an in-page overlay with the full code, verdict detail, and for failed runs, exactly which test case failed and how. There's a copy link button to share a submission, and a profile setting to control whether others can view your accepted solutions.

Clearer verdicts

• New Output Limit Exceeded verdict: if your code prints past the output cap, you'll see that, with the output you did produce, instead of a mystery Runtime Error.
• Runtime errors got richer: real stack traces and clearer messages, plus deep recursion now works to a sane limit in every language.

Catalog

• Company tags: problems now say which companies have asked them, sourced from interview reports.
• Report a problem: found a broken test case or a confusing description? There's now a report button with categories, and reports land directly with us.
• Twelve new problems, including Invert Binary Tree, Cheapest Flights Within K Stops, Subarrays with K Different Integers, and a run of fresh questions from Uber, Infosys, TCS, and Broadridge interviews.
• Several ladders (Heaps, Trie, Dijkstra, Topological Sort, Stacks & Queues) picked up easier on-ramp rungs so the first step isn't a wall.
• Your activity feed now includes discuss posts from people you follow.