Order book Yuriy Lyfenko

Simulate a sell-side order book and calculate the cost of a final purchase as fast as possible.

Input

1,000,000 order updates on STDIN, one per line:

  • + <price> <size> – add a new sell order
  • - <position> – delete the order at the given position
  • = <size> – buy <size> shares from the top of the order book

After all updates are processed, buy 1,000 shares from the top of the order book.

Output

Print the total cost of the final 1,000-share purchase to STDOUT.

Order Book Rules

Orders are sorted by price ascending (lower is better). Orders at the same price are sorted by arrival time (earlier first). Position 0 is the best (lowest-price) offer.

The = (buy) operation consumes shares starting from position 0. If an order is fully consumed, it is removed from the book.

Example

Input Order book state
+ 1137 100 (1137,100)
+ 1130 10 (1130,10), (1137,100)
+ 1130 50 (1130,10), (1130,50), (1137,100)
- 0 (1130,50), (1137,100)
+ 1150 200 (1130,50), (1137,100), (1150,200)
= 200 (1150,150)

Total cost of the last buy: 50 * 1130 + 100 * 1137 + 50 * 1150.

Back to listFeb 27, 2026 23:280xZohan0xZohanScore: 100,829Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Feb 27, 2026 23:28100,33485,400,08854,181,0004,013,0002,510,848
2Feb 27, 2026 23:28100,73384,698,11053,389,0005,036,0002,478,080
3Feb 27, 2026 23:28100,73385,071,17853,389,0005,036,0002,355,200
4Feb 27, 2026 23:28100,75286,775,24453,399,0005,037,0002,326,528
5Feb 27, 2026 23:28100,82985,501,47153,440,0005,041,0002,375,680
6Feb 27, 2026 23:28100,86484,046,52953,458,0005,043,0002,293,760
7Feb 27, 2026 23:28100,95787,731,53853,508,0005,047,0002,453,504
8Feb 27, 2026 23:28101,29185,895,69054,766,0003,983,0002,285,568
9Feb 27, 2026 23:28101,66787,440,35454,970,0003,997,0002,338,816