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 13, 2025 15:02Emanuele BolognesiEmanuele BolognesiError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1May 13, 2025 15:0200000Error: expected "1693778 ", got "3244 268724 7214453 7467097 141219 18775 11560254 16360225 1628245 8760419 19902571 11153685 1160755 1953288 13680786 19367227 164912 27390949 2407711 2368708 4050801 115752 370388 1877728 26587668 15187687 21618534 173...