uz · ru · en

Practice coding. Get hints, not answers.

Solve tasks in Python, JavaScript, C++ or Java, run them against hidden tests in seconds, and ask the AI tutor for a nudge when you're stuck.

solution.pypython3
1n = int(input())
2a = list(map(int, input().split()))
3best = cur = a[0]
4for x in a[1:]:
5 cur = max(x, cur + x)
6 best = max(best, cur)
7print(best)
Judging… Accepted7 / 7 tests38 ms
+25 XP · streak 🔥 4
Hint 2 / 3
30+
tasks with editorials
4
programming languages
3
levels of hints
3
interface languages
Python 3JavaScriptC++JavaMonacoSandbox1v1ELOXPStreaksGeminiuz · ru · enPython 3JavaScriptC++JavaMonacoSandbox1v1ELOXPStreaksGeminiuz · ru · en

Everything a learner needs

From the first loop to a live 1v1 — one place, three languages.

Practice

30+ curated tasks from easy to hard — loops, strings, arrays, hashing, recursion, sorting, two pointers — with statements in Uzbek, Russian and English.

Instant verdicts

Your code runs against hidden tests in an isolated sandbox: Accepted, Wrong answer, Time limit or Runtime error within seconds, with time and memory.

AI tutor

Three levels of hints that nudge you toward the idea: understand the task, find the approach, unblock your code. It never hands over the solution.

1v1 battles

Find an opponent, get the same task, race to the first Accepted. ELO-style ratings, rematches and spectators.

For schools

Teachers create classes, assign tasks, review submissions with comments and watch a class leaderboard.

Progress that shows

XP, levels, daily streaks and achievements. Editorials unlock after you solve a task — learn the intended idea.

How it works

Four steps, a few minutes each.

1

Pick a task

Filter by difficulty and topic. Every statement comes in your language.

2

Write code

Monaco editor in the browser — the same engine as VS Code, with templates for every language.

3

Get a verdict

Hidden tests run in a sandbox. See exactly which case failed and how fast you ran.

4

Learn the idea

Stuck? Ask the tutor. Solved? Read the editorial and compare approaches.

Race a rival to Accepted

Battles are 1v1: the same task, 15 minutes, first Accepted wins. Ratings move ELO-style, and the tutor sits this one out.

  • First Accepted wins
  • ELO-style rating
  • Live battles
  • Rematch in one click
Y
You
1000 → 1016
+16
VS
R
Rival
1000 → 984
14:32

A tutor that nudges, not solves

Hints unlock in order and are limited per day, so you keep thinking. Every hint is logged and reviewed for quality.

Never hands over the solution

1

Level 1 · Understand

Restates the task and points at what to look for in the input.

2

Level 2 · Approach

Names the idea — a hash map, two pointers, a sieve — without the code.

3

Level 3 · Unblock

Looks at your code and says where it goes wrong. Still no solution.

Built for classrooms

An organization is a school or a course. Teachers see who solved what, students see their assignments.

Classes by invite

Students join with a code or a link; no admin work.

Assignments

Assign tasks to the whole class or to specific students.

Review with comments

Open any submission, leave feedback, the student replies.

Class leaderboard

Solved counts and streaks per class, private to the org.

Start with an easy one

Free for learners. No credit card, no setup — the editor is in your browser.