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 2, 2026 22:12JuneLJuneLScore: 53,948Success
Source Code

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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Mar 2, 2026 22:1152,69558,088,76729,545,0001,018,0002,441,216
2Mar 2, 2026 22:1152,90255,015,99430,683,00002,510,848
3Mar 2, 2026 22:1153,24858,371,10628,892,0001,992,0002,523,136
4Mar 2, 2026 22:1253,39561,222,11728,971,0001,998,0002,433,024
5Mar 2, 2026 22:1253,41658,252,10228,983,0001,998,0002,433,024
6Mar 2, 2026 22:1253,50564,960,07429,031,0002,002,0002,334,720
7Mar 2, 2026 22:1253,52863,636,69530,045,0001,001,0002,510,848
8Mar 2, 2026 22:1153,54860,555,20430,057,0001,001,0002,289,664
9Mar 2, 2026 22:1253,58855,174,65229,076,0002,005,0002,375,680
10Mar 2, 2026 22:1253,81253,010,93429,198,0002,013,0002,281,472
11Mar 2, 2026 22:1153,82456,762,37230,211,0001,007,0002,310,144
12Mar 2, 2026 22:1253,85259,158,16830,227,0001,007,0002,400,256
13Mar 2, 2026 22:1253,88651,883,50129,238,0002,016,0002,416,640
14Mar 2, 2026 22:1153,91754,842,33829,255,0002,017,0002,367,488
15Mar 2, 2026 22:1253,92955,177,12229,261,0002,018,0002,527,232
16Mar 2, 2026 22:1253,94854,089,98130,281,0001,009,0002,465,792
17Mar 2, 2026 22:1254,02153,923,28130,322,0001,010,0002,416,640
18Mar 2, 2026 22:1254,07154,074,91030,350,0001,011,0002,408,448
19Mar 2, 2026 22:1254,10554,115,42630,369,0001,012,0002,367,488
20Mar 2, 2026 22:1254,15256,562,72130,395,0001,013,0002,379,776
21Mar 2, 2026 22:1254,16660,714,80630,403,0001,013,0002,355,200
22Mar 2, 2026 22:1154,20255,567,56130,423,0001,014,0002,383,872
23Mar 2, 2026 22:1254,24057,693,19930,445,0001,014,0002,334,720
24Mar 2, 2026 22:1254,24154,076,54831,460,00002,469,888
25Mar 2, 2026 22:1154,39158,114,27231,547,00002,473,984
26Mar 2, 2026 22:1154,40257,650,96531,553,00002,424,832
27Mar 2, 2026 22:1254,45252,670,15331,582,00002,379,776
28Mar 2, 2026 22:1254,49853,820,00730,590,0001,019,0002,490,368
29Mar 2, 2026 22:1254,50765,743,38130,595,0001,019,0002,281,472
30Mar 2, 2026 22:1254,52959,157,71730,607,0001,020,0002,482,176