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Python pattern
Aggregation & grouping
7 problems in this pattern, climbing easy → medium → hard. Pick wherever you're calibrated.
Easy
0 / 2 solved
Count events by type
Python
· ~5 min
NEW
Per-customer order count and revenue
Python
· ~9 min
NEW
Medium
0 / 1 solved
Total and shipped order counts per customer
Python
· ~11 min
NEW
Hard
0 / 4 solved
Sum revenue per customer over dirty records
Python
· ~15 min
NEW
Each row's percent of its customer total
Python
· ~12 min
NEW
Quantity-weighted average price per product
Python
· ~13 min
NEW
Merge partial aggregates from parallel workers
Python
· ~25 min
NEW