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 listOct 4, 2026 14:24Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 4, 2026 14:24039,891,00427,742,0001,047,0002,113,536expected "644683 ", got "B8899010 a732811 d256582 b10607 p321-1735 s1-500 dmax805 dmean266 d0 479 bmax94625 balmax476229 bal476229 "
2Oct 4, 2026 14:24039,789,03827,606,0001,032,0002,113,536expected "1793607 ", got "B8943454 a730832 d258608 b10560 p292-2187 s1-500 dmax869 dmean268 d0 552 bmax129341 balmax472225 bal472224 "
3Oct 4, 2026 14:24040,088,84628,037,0001,032,0002,113,536expected "1411667 ", got "B9381838 a730271 d259288 b10441 p541-2551 s1-500 dmax818 dmean269 d0 472 bmax69485 balmax470984 bal470983 "