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 | |
|---|---|---|---|---|---|
| Aug 31, 2026 16:33 | ZIG0.16.0 | Error | |||
| Aug 31, 2026 16:33 | CPPclang++18.1.3 | Error | |||
| Aug 31, 2026 16:29 | CSHARP10.0.7 | Error | |||
| Aug 31, 2026 16:28 | RUSTrust-1.95.0 | Error | |||
| Aug 31, 2026 16:27 | GOgo1.26.2 | Error | |||
| Aug 31, 2026 16:09 | CPPg++14.2.0 | Error | |||
| Aug 31, 2026 16:00 | CSHARP10.0.7 | Error | |||
| Aug 31, 2026 15:56 | CPPg++14.2.0 | Error | |||
| Aug 31, 2026 15:51 | ZIG0.16.0 | Error | |||
| Aug 31, 2026 15:50 | RUSTrust-1.95.0 | Error | |||
| Aug 31, 2026 15:39 | GOgo1.26.2 | Error | |||
| Aug 31, 2026 15:34 | RUSTrust-1.95.0 | Error | |||
| Aug 31, 2026 15:33 | CPPg++14.2.0 | Success | 46,701 | ||
| Aug 31, 2026 15:29 | CPPg++14.2.0 | Error | +16.89 RP | ||
| Aug 31, 2026 15:29 | CPPg++14.2.0 | Error | |||
| Aug 31, 2026 15:15 | GOgo1.26.2 | Error | |||
| Aug 31, 2026 15:01 | GOgo1.26.2 | Error | |||
| Aug 31, 2026 13:43 | CPPclang++20.1.2 | Error | |||
| Aug 31, 2026 13:42 | CPPclang++20.1.2 | Error | |||
| Aug 31, 2026 13:40 | CPPclang++20.1.2 | Error | |||
| Aug 31, 2026 13:36 | CPPclang++20.1.2 | Error | +154.48 RP | ||
| Aug 31, 2026 13:35 | CPPclang++20.1.2 | Error | +291.98 RP | ||
| Aug 31, 2026 13:31 | CPPclang++20.1.2 | Error | |||
| Aug 31, 2026 13:29 | CPPclang++20.1.2 | Error | +428.68 RP | ||
| Aug 31, 2026 13:26 | CPPclang++20.1.2 | Error | +871.38 RP | ||
| Aug 31, 2026 13:24 | CPPclang++20.1.2 | Error | +3'017.69 RP | ||
| Aug 31, 2026 13:21 | CPPclang++20.1.2 | Error | |||
| Aug 31, 2026 03:38 | CPPclang++20.1.2 | Error | |||
| Aug 31, 2026 03:24 | CPPclang++20.1.2 | Success | 126,175 | ||
| Aug 31, 2026 03:23 | CPPclang++20.1.2 | Success | 118,420 | ||
| Aug 31, 2026 03:22 | CPPclang++20.1.2 | Success | 117,560 | ||
| Aug 31, 2026 03:18 | CPPclang++20.1.2 | Success | 119,394 | ||
| Aug 29, 2026 17:47 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 17:38 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 16:30 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 15:28 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 15:14 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 14:51 | CPPg++14.2.0 | Error | +124.81 RP | ||
| Aug 29, 2026 14:44 | RUSTrust-1.95.0 | Success | 185,281+0.86 RP | ||
| Aug 29, 2026 14:23 | RUSTrust-1.95.0 | Error | +53.11 RP | ||
| Aug 29, 2026 14:13 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 13:52 | CPPg++14.2.0 | Error | +108.54 RP | ||
| Aug 29, 2026 13:39 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 13:24 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 12:51 | CPPg++14.2.0 | Error | +47.92 RP | ||
| Aug 29, 2026 12:38 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 12:31 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 10:57 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 09:52 | CPPg++14.2.0 | Error | |||
| Aug 29, 2026 09:06 | CPPg++14.2.0 | Error | |||
| Aug 27, 2026 08:22 | CSHARP10.0.11 | Success | 311,386 | ||
| Aug 27, 2026 08:09 | CSHARP10.0.11 | Success | 364,506 | ||
| Aug 27, 2026 08:00 | CSHARP10.0.11 | Success | 285,931+19.87 RP | ||
| Aug 27, 2026 07:33 | CSHARP10.0.11 | Error | |||
| Aug 27, 2026 07:17 | CSHARP10.0.11 | Success | 662,058+5.07 RP | ||
| Aug 27, 2026 06:38 | CSHARP9.0.15 | Error | |||
| Aug 27, 2026 06:36 | CSHARP10.0.11 | Error | |||
| Aug 25, 2026 16:06 | CPPg++14.2.0 | Success | 1,284,641 | ||
| Aug 23, 2026 17:51 | CPPclang++20.1.2 | Success | 85,613 | ||
| Aug 23, 2026 16:58 | RUSTrust-1.95.0 | Success | 122,325 | ||
| Aug 23, 2026 16:34 | CPPg++14.2.0 | Success | 50,482+7.25 RP | ||
| Aug 23, 2026 16:10 | CPPg++14.2.0 | Success | 52,401+156.88 RP | ||
| Aug 23, 2026 15:38 | CPPg++14.2.0 | Success | 294,474+26.25 RP | ||
| Aug 21, 2026 19:35 | CPPg++14.2.0 | Success | 1,297,227+7.71 RP | ||
| Aug 20, 2026 07:58 | CPPg++10.5.0 | Success | 81,087+26.64 RP | ||
| Aug 19, 2026 21:31 | CPPg++10.5.0 | Success | 126,615 | ||
| Aug 19, 2026 18:37 | CPPg++10.5.0 | Success | 103,431+10.83 RP | ||
| Aug 19, 2026 17:50 | CPPg++10.5.0 | Success | 122,055 | ||
| Aug 19, 2026 15:15 | CPPg++10.5.0 | Success | 198,101 | ||
| Aug 19, 2026 14:57 | CPPg++10.5.0 | Success | 268,508 | ||
| Aug 19, 2026 14:47 | CPPg++10.5.0 | Success | 266,036 | ||
| Aug 19, 2026 06:06 | CPPg++10.5.0 | Success | 213,160 | ||
| Aug 18, 2026 19:39 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 19:33 | CPPclang++20.1.2 | Error | +8.88 RP | ||
| Aug 18, 2026 19:30 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 19:27 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 19:24 | CPPclang++20.1.2 | Success | 45,206 | ||
| Aug 18, 2026 19:22 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 19:21 | CPPclang++20.1.2 | Error | +1.89 RP | ||
| Aug 18, 2026 19:15 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 18:55 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 18:52 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 18:50 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 16:11 | CPPg++10.5.0 | Success | 116,481+1.71 RP | ||
| Aug 18, 2026 16:01 | CPPg++10.5.0 | Error | +50.67 RP | ||
| Aug 18, 2026 15:21 | CPPg++10.5.0 | Success | 298,696+13.38 RP | ||
| Aug 18, 2026 14:21 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 14:20 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 14:19 | CPPg++10.5.0 | Error | |||
| Aug 18, 2026 14:18 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 14:16 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 14:14 | CPPclang++20.1.2 | Error | +4.44 RP | ||
| Aug 18, 2026 14:14 | CPPclang++20.1.2 | Error | +1.20 RP | ||
| Aug 18, 2026 14:11 | CPPclang++20.1.2 | Error | +32.76 RP | ||
| Aug 18, 2026 14:05 | CPPclang++20.1.2 | Success | 46,836+26.34 RP | ||
| Aug 18, 2026 14:02 | CPPclang++20.1.2 | Error | |||
| Aug 18, 2026 13:54 | CPPclang++20.1.2 | Success | 57,832 | ||
| Aug 18, 2026 13:46 | CPPclang++20.1.2 | Success | 53,427+4.53 RP | ||
| Aug 18, 2026 13:41 | CPPclang++20.1.2 | Success | 56,179 | ||
| Aug 18, 2026 13:39 | CPPclang++20.1.2 | Error |