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 05:34Carl BergmanCarl BergmanError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Apr 11, 2025 05:3400000Error: expected "1627000 ", got "5352946 11819386 2552633 822511 1504495 19461485 2242778 5740153 3007850 3857630 20810108 33592663 17327729 773 4886 221705 18389229 10796713 2118562 31526352 11140826 33274987 32304913 17722789 21479500 12434936 117345...