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 15:04Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 4, 2026 15:040139,365,224127,487,0001,120,0002,113,536expected "2750329 ", got "maxlv 23 span dec: 148 339 392 442 504 568 690 891 1025 1188 1730 | 99% 1519 2750329 "
2Oct 4, 2026 15:040139,741,090128,277,0001,021,0002,113,536expected "2079251 ", got "maxlv 16 span dec: 198 461 510 547 583 624 664 714 772 857 1351 | 99% 1076 2079251 "
3Oct 4, 2026 15:040139,877,756128,392,0001,057,0002,113,536expected "953363 ", got "maxlv 17 span dec: 204 440 490 530 565 598 635 682 742 824 1085 | 99% 964 953363 "