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 listApr 11, 2025 05:30Carl BergmanCarl BergmanError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Apr 11, 2025 05:3000000Error: expected "750284 ", got "8767258 5229 2254119 26899688 1303231 5560839 213720 13642315 26115172 21866 4690451 22629968 2181 16987865 7767269 596337 6493457 1622096 33376160 842 15351497 28371927 68706 14803769 16581773 20869353 8080404 13206159 ...