Level 1 · Foundations · Data and input
Deduplicate events
Keep the latest event per ID in a stable order.
45-minute timed challenge
- Accuracy
- 50
- Performance
- 30
- Submission time
- 20
Accuracy: 50 points · Performance: 30 · Time: 20. Other scores count only with at least 35 accuracy points. Each problem gives one 45-minute attempt with up to five submissions. Your best score is kept.
Starting a timed challenge or submitting an introductory task costs 5P. Resuming an attempt and system regrading are free.
Time is measured from start to submission. Each submission records its time score, excluding grading wait time. The deadline for additional submissions continues to run.
View scoring details
The benchmark uses 20000 inputs. We measure execution three times, excluding setup and validation, and use the median. Up to 30ms earns 30 points; up to 2.5× earns 24, 5× earns 18, 10× earns 9, and slower earns 0.
Checking your attempt…