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 listMar 24, 2026 14:20DmtryDmtryScore: 4,288Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Mar 24, 2026 14:174,22916,744,7172,453,00002,461,696
2Mar 24, 2026 14:174,23319,096,4872,455,00002,461,696
3Mar 24, 2026 14:174,23819,263,6111,229,0001,229,0002,461,696
4Mar 24, 2026 14:174,24018,512,0622,459,00002,465,792
5Mar 24, 2026 14:164,27816,191,0302,481,00002,531,328
6Mar 24, 2026 14:164,28323,060,3762,484,00002,461,696
7Mar 24, 2026 14:174,28618,510,7392,486,00002,535,424
8Mar 24, 2026 14:174,28816,246,6362,487,00002,461,696
9Mar 24, 2026 14:174,29820,928,0692,493,00002,461,696
10Mar 24, 2026 14:204,31018,190,9512,500,00002,535,424
11Mar 24, 2026 14:204,31018,629,7652,500,00002,465,792
12Mar 24, 2026 14:174,34118,649,6591,259,0001,259,0002,461,696
13Mar 24, 2026 14:174,42918,105,6782,569,00002,461,696
14Mar 24, 2026 14:204,46617,259,4612,590,00002,457,600
15Mar 24, 2026 14:164,75718,671,3862,759,00002,531,328