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 listMay 9, 2025 16:44Amit RahmanAmit RahmanScore: 1,299,402Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1May 9, 2025 16:441,265,772756,250,089731,148,0003,000,0002,273,280
2May 9, 2025 16:441,266,672760,762,248732,671,0001,999,0002,277,376
3May 9, 2025 16:441,279,198763,836,833739,936,0001,999,0002,273,280
4May 9, 2025 16:441,279,802768,673,107738,289,0003,996,0002,277,376
5May 9, 2025 16:441,299,402777,297,249751,654,0001,999,0002,277,376
6May 9, 2025 16:441,301,926778,492,984752,117,0003,000,0002,273,280
7May 9, 2025 16:441,308,772784,991,252757,088,0002,000,0002,486,272
8May 9, 2025 16:441,321,093796,599,816763,234,0003,000,0002,273,280
9May 9, 2025 16:441,381,938825,389,903799,526,0001,998,0002,482,176