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 listAug 29, 2026 15:14Victor MerckléVictor MerckléScore: 2,787Success
Source Code

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Challenge History
DateChallengerCostTypeStatus
Sep 10, 2026 17:22Tomislav Tunkovic10.00CustomSolution Held
Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Aug 29, 2026 15:152,6109,648,6031,514,00002,117,632stderr
2Aug 29, 2026 15:152,6189,621,0901,519,00002,117,632stderr
3Aug 29, 2026 15:152,6229,753,4581,521,00002,117,632stderr
4Aug 29, 2026 15:152,6639,621,7131,545,00002,117,632stderr
5Aug 29, 2026 15:152,7879,694,6671,617,00002,117,632stderr
6Aug 29, 2026 15:152,81510,386,8211,633,00002,117,632stderr
7Aug 29, 2026 15:1531,31826,513,50218,165,00002,117,632stderr
8Aug 29, 2026 15:15238,405147,349,108132,529,0005,746,0002,117,632stderr
9Aug 29, 2026 15:15242,618149,103,462135,270,0005,449,0002,117,632stderr