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 listSep 25, 2026 21:47Kevin HeaveyKevin HeaveyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Sep 25, 2026 21:470225,782,029212,222,0003,028,00024,576Exit with code 3: ans=704000 P*=704 full mx814 avg528 | mins 817 744 1016 776 761 391 457 704 | T+0 aok mx769 avg119 t268644 | T+5 aok mx769 avg121 t273229 | T+20 aok mx770 avg127 t287052 | T+50 aok mx770 avg141 t315241stderr