Order book 
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.
| Date | Author | Language | Status | Score | |
|---|---|---|---|---|---|
| Jun 20, 2026 17:47 | RUSTrust-1.95.0 | Success | 5,724 | ||
| Jun 20, 2026 17:40 | RUSTrust-1.95.0 | Success | 5,913 | ||
| Jun 20, 2026 17:14 | RUSTrust-1.95.0 | Success | 5,960 | ||
| Jun 20, 2026 17:09 | RUSTrust-1.95.0 | Success | 5,781 | ||
| Jun 20, 2026 17:05 | RUSTrust-1.95.0 | Success | 5,634+17.78 RP | ||
| Jun 20, 2026 16:54 | RUSTrust-1.95.0 | Success | 5,777 | ||
| Jun 20, 2026 16:28 | RUSTrust-1.95.0 | Success | 5,691+81.56 RP | ||
| Jun 20, 2026 15:45 | RUSTrust-1.95.0 | Success | 44,562 | ||
| Jun 20, 2026 15:18 | RUSTrust-1.95.0 | Success | 6,125 | ||
| Jun 20, 2026 07:46 | CPPg++10.5.0 | Error | |||
| Jun 20, 2026 06:14 | RUSTrust-1.95.0 | Success | 6,146 | ||
| Jun 20, 2026 03:33 | RUSTrust-1.95.0 | Error | |||
| Jun 19, 2026 16:02 | RUSTrust-1.95.0 | Success | 44,374 | ||
| Jun 19, 2026 15:48 | RUSTrust-1.95.0 | Success | 6,093 | ||
| Jun 19, 2026 15:08 | CPPg++14.2.0 | Success | 4,993 | ||
| Jun 19, 2026 15:03 | CPPg++14.2.0 | Success | 3,272 | ||
| Jun 19, 2026 14:58 | CPPg++14.2.0 | Success | 3,281 | ||
| Jun 19, 2026 14:56 | RUSTrust-1.95.0 | Success | 5,968+1'390.36 RP | ||
| Jun 19, 2026 14:53 | CPPg++14.2.0 | Success | 3,244 | ||
| Jun 19, 2026 06:02 | CPPg++14.2.0 | Success | 3,298 | ||
| Jun 19, 2026 05:54 | CPPg++14.2.0 | Success | 3,317 | ||
| Jun 18, 2026 21:38 | CPPg++14.2.0 | Success | 3,253 | ||
| Jun 18, 2026 21:32 | CPPg++14.2.0 | Success | 3,839 | ||
| Jun 18, 2026 21:27 | CPPg++14.2.0 | Success | 3,244 | ||
| Jun 18, 2026 21:22 | CPPg++14.2.0 | Success | 5,258 | ||
| Jun 18, 2026 14:16 | CPPg++14.2.0 | Success | 38,227 | ||
| Jun 18, 2026 14:11 | CPPg++14.2.0 | Error | |||
| Jun 18, 2026 14:06 | CPPg++14.2.0 | Error | |||
| Jun 18, 2026 14:01 | CPPg++14.2.0 | Success | 3,322 | ||
| Jun 18, 2026 13:54 | CPPg++14.2.0 | Success | 3,477 | ||
| Jun 18, 2026 03:32 | CPPg++14.2.0 | Error | |||
| Jun 18, 2026 03:27 | CPPg++14.2.0 | Success | 4,968 | ||
| Jun 18, 2026 03:22 | CPPg++14.2.0 | Success | 3,372 | ||
| Jun 18, 2026 03:17 | CPPg++14.2.0 | Error | |||
| Jun 18, 2026 03:12 | CPPg++14.2.0 | Success | 3,289 | ||
| Jun 18, 2026 02:58 | CPPg++14.2.0 | Success | 38,210 | ||
| Jun 17, 2026 21:19 | CPPg++14.2.0 | Error | |||
| Jun 17, 2026 21:14 | CPPg++14.2.0 | Success | 3,348 | ||
| Jun 17, 2026 21:09 | CPPg++14.2.0 | Success | 3,277 | ||
| Jun 17, 2026 21:04 | CPPg++14.2.0 | Success | 3,539 | ||
| Jun 17, 2026 20:59 | CPPg++14.2.0 | Success | 3,400 | ||
| Jun 17, 2026 18:49 | CPPg++14.2.0 | Success | 38,379 | ||
| Jun 17, 2026 18:44 | CPPg++14.2.0 | Success | 3,150+5.03 RP | ||
| Jun 17, 2026 18:33 | CPPg++14.2.0 | Error | |||
| Jun 15, 2026 23:16 | ZIG0.16.0 | Success | 3,279 | ||
| Jun 15, 2026 23:11 | ZIG0.16.0 | Success | 3,253 | ||
| Jun 15, 2026 23:06 | ZIG0.16.0 | Success | 3,232 | ||
| Jun 15, 2026 23:01 | ZIG0.16.0 | Success | 5,241 | ||
| Jun 15, 2026 22:56 | ZIG0.16.0 | Success | 3,224+53.89 RP | ||
| Jun 15, 2026 22:51 | ZIG0.16.0 | Error | |||
| Jun 15, 2026 22:46 | ZIG0.16.0 | Success | 37,068 | ||
| Jun 15, 2026 22:41 | ZIG0.16.0 | Success | 3,341 | ||
| Jun 15, 2026 22:32 | ZIG0.16.0 | Success | 3,381 | ||
| Jun 15, 2026 11:25 | GOgo1.26.2 | Success | 1,291,439+7.74 RP | ||
| Jun 13, 2026 18:26 | GOgo1.26.2 | Success | 35,943 | ||
| Jun 13, 2026 18:08 | GOgo1.26.2 | Success | 34,010 | ||
| Jun 13, 2026 18:02 | GOgo1.26.2 | Error | |||
| Jun 13, 2026 17:45 | CSHARP10.0.7 | Success | 33,862 | ||
| Jun 13, 2026 17:40 | CSHARP10.0.7 | Success | 33,543 | ||
| Jun 13, 2026 17:24 | CSHARP10.0.7 | Success | 33,753 | ||
| Jun 13, 2026 01:04 | CSHARP10.0.7 | Success | 36,567 | ||
| Jun 13, 2026 00:47 | CSHARP10.0.7 | Success | 36,639 | ||
| Jun 13, 2026 00:28 | CSHARP10.0.7 | Error | |||
| Jun 13, 2026 00:09 | CSHARP10.0.7 | Error | |||
| Jun 12, 2026 23:17 | CSHARP10.0.7 | Success | 5,139+582.76 RP | ||
| Jun 12, 2026 23:11 | GOgo1.26.2 | Success | 4,632 | ||
| Jun 12, 2026 23:06 | GOgo1.26.2 | Error | |||
| Jun 12, 2026 22:51 | GOgo1.26.2 | Success | 4,679 | ||
| Jun 12, 2026 22:46 | GOgo1.26.2 | Success | 4,575+920.77 RP | ||
| Jun 12, 2026 20:35 | RUSTrust-1.95.0 | Success | 3,227 | ||
| Jun 12, 2026 20:03 | RUSTrust-1.95.0 | Success | 38,493 | ||
| Jun 12, 2026 19:53 | RUSTrust-1.95.0 | Error | |||
| Jun 12, 2026 19:42 | RUSTrust-1.95.0 | Error | |||
| Jun 12, 2026 19:31 | RUSTrust-1.95.0 | Success | 3,298 | ||
| Jun 12, 2026 13:01 | CPPg++14.2.0 | Success | 37,086 | ||
| Jun 12, 2026 12:56 | CPPg++14.2.0 | Error | |||
| Jun 12, 2026 12:48 | CPPg++14.2.0 | Success | 3,336 | ||
| Jun 12, 2026 12:43 | CPPg++14.2.0 | Error | |||
| Jun 12, 2026 12:38 | CPPg++14.2.0 | Error | |||
| Jun 12, 2026 12:31 | CPPg++14.2.0 | Error | |||
| Jun 12, 2026 12:26 | CPPg++14.2.0 | Success | 3,287 | ||
| Jun 12, 2026 12:21 | CPPg++14.2.0 | Success | 3,358 | ||
| Jun 12, 2026 12:16 | CPPg++14.2.0 | Success | 38,237+5.00 RP | ||
| Jun 11, 2026 14:09 | ZIG0.16.0 | Success | 37,587 | ||
| Jun 11, 2026 13:51 | ZIG0.16.0 | Success | 3,281+153.50 RP | ||
| Jun 11, 2026 13:25 | ZIG0.16.0 | Success | 3,455+928.56 RP | ||
| Jun 11, 2026 08:29 | RUSTrust-1.95.0 | Success | 35,058+11.90 RP | ||
| Jun 11, 2026 08:26 | ZIG0.16.0 | Success | 10,468 | ||
| Jun 11, 2026 08:22 | CPPg++14.2.0 | Success | 48,808+10.69 RP | ||
| Jun 11, 2026 08:17 | CPPclang++20.1.2 | Success | 51,496+19.97 RP | ||
| Jun 11, 2026 07:35 | RUSTrust-1.95.0 | Success | 36,584+18.28 RP | ||
| Jun 11, 2026 07:29 | CPPg++14.2.0 | Success | 57,400+48.44 RP | ||
| Jun 11, 2026 07:13 | CPPg++14.2.0 | Success | 82,008 | ||
| Jun 11, 2026 07:05 | RUSTrust-1.95.0 | Success | 183,620 | ||
| Jun 11, 2026 06:29 | RUSTrust-1.95.0 | Success | 185,091 | ||
| Jun 10, 2026 21:54 | CPPg++14.2.0 | Error | |||
| Jun 10, 2026 21:49 | CPPg++14.2.0 | Success | 3,465 | ||
| Jun 10, 2026 21:44 | CPPg++14.2.0 | Success | 5,655 | ||
| Jun 10, 2026 21:39 | CPPg++14.2.0 | Error | |||
| Jun 10, 2026 21:34 | CPPg++14.2.0 | Success | 3,325 |