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 15, 2025 17:32Priyanshu GuptaPriyanshu GuptaScore: 1,298,410Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 15, 2025 17:321,250,812756,581,790720,475,0004,996,0002,273,280
2Oct 15, 2025 17:321,286,152772,755,699743,969,0001,999,0002,277,376
3Oct 15, 2025 17:321,286,874768,568,560742,391,0003,996,0002,273,280
4Oct 15, 2025 17:321,293,107781,234,590747,002,0003,000,0002,273,280
5Oct 15, 2025 17:321,298,410774,115,760751,078,0002,000,0002,326,528
6Oct 15, 2025 17:321,299,440779,518,844747,678,0005,997,0002,490,368
7Oct 15, 2025 17:321,303,066783,280,128752,779,0002,999,0002,482,176
8Oct 15, 2025 17:321,309,953783,107,297755,775,0003,998,0002,265,088
9Oct 15, 2025 17:321,326,147797,603,799768,165,0001,000,0002,273,280