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 | |
|---|---|---|---|---|---|
| Feb 6, 2026 20:45 | CPPg++13.3.0 | Success | 91,164 | ||
| Feb 6, 2026 20:44 | CPPg++13.3.0 | Success | 75,898+1.92 RP | ||
| Feb 6, 2026 20:44 | CPPg++13.3.0 | Success | 81,755 | ||
| Feb 6, 2026 20:30 | CPPg++13.3.0 | Success | 77,022+19.01 RP | ||
| Feb 6, 2026 20:20 | CPPg++13.3.0 | Error | |||
| Feb 6, 2026 20:19 | CPPg++13.3.0 | Error | |||
| Feb 6, 2026 20:19 | CPPg++13.3.0 | Success | 90,233+89.16 RP | ||
| Feb 6, 2026 20:18 | CPPg++13.3.0 | Error | |||
| Feb 6, 2026 20:08 | CPPg++13.3.0 | Success | 461,538+21.67 RP | ||
| Feb 3, 2026 22:16 | CPPg++13.3.0 | Success | 95,378 | ||
| Feb 3, 2026 22:16 | CPPg++13.3.0 | Success | 64,905 | ||
| Feb 3, 2026 22:16 | CPPg++13.3.0 | Success | 60,493 | ||
| Feb 3, 2026 22:16 | CPPg++13.3.0 | Success | 69,805 | ||
| Feb 3, 2026 22:02 | CPPg++13.3.0 | Success | 89,159 | ||
| Feb 3, 2026 21:48 | CPPg++13.3.0 | Success | 68,716 | ||
| Feb 3, 2026 21:47 | CPPg++13.3.0 | Success | 69,243 | ||
| Feb 3, 2026 21:47 | CPPg++13.3.0 | Success | 86,541 | ||
| Feb 3, 2026 21:46 | CPPg++13.3.0 | Success | 67,359 | ||
| Feb 2, 2026 05:27 | RUSTrust-1.93.0 | Success | 124,150+2.49 RP | ||
| Feb 2, 2026 05:07 | RUSTrust-1.93.0 | Success | 128,116+78.05 RP | ||
| Jan 30, 2026 17:11 | RUSTrust-1.93.0 | Success | 86,228 | ||
| Jan 30, 2026 17:10 | RUSTrust-1.93.0 | Success | 85,691 | ||
| Jan 30, 2026 17:10 | RUSTrust-1.93.0 | Success | 1,130,429 | ||
| Jan 30, 2026 17:09 | RUSTrust-1.93.0 | Success | 90,009 | ||
| Jan 30, 2026 17:08 | CPPg++13.3.0 | Success | 9,881 | ||
| Jan 30, 2026 17:07 | CPPg++13.3.0 | Error | |||
| Jan 30, 2026 17:06 | CPPg++13.3.0 | Success | 9,231+66.84 RP | ||
| Jan 30, 2026 17:06 | CPPg++13.3.0 | Error | |||
| Jan 30, 2026 17:04 | CPPg++13.3.0 | Success | 9,838+58.43 RP | ||
| Jan 30, 2026 17:03 | CPPg++13.3.0 | Success | 10,438+107.84 RP | ||
| Jan 30, 2026 17:02 | CPPg++13.3.0 | Success | 11,762+156.67 RP | ||
| Jan 30, 2026 17:01 | CPPg++13.3.0 | Error | |||
| Jan 30, 2026 16:59 | CPPg++13.3.0 | Success | 14,419+544.69 RP | ||
| Jan 30, 2026 16:39 | CPPg++13.3.0 | Success | 114,229 | ||
| Jan 30, 2026 16:39 | CPPg++13.3.0 | Success | 115,367 | ||
| Jan 30, 2026 16:36 | RUSTrust-1.93.0 | Success | 271,728 | ||
| Jan 30, 2026 16:36 | RUSTrust-1.93.0 | Success | 67,186+40.55 RP | ||
| Jan 30, 2026 15:58 | CPPg++13.3.0 | Success | 99,793 | ||
| Jan 30, 2026 15:41 | CPPg++13.3.0 | Success | 92,341+5.55 RP | ||
| Jan 30, 2026 15:40 | CPPg++13.3.0 | Success | 107,578 | ||
| Jan 30, 2026 15:32 | RUSTrust-1.93.0 | Success | 134,445 | ||
| Jan 30, 2026 14:27 | RUSTrust-1.93.0 | Success | 97,326+10.02 RP | ||
| Jan 30, 2026 14:26 | RUSTrust-1.93.0 | Success | 113,705 | ||
| Jan 30, 2026 14:25 | CPPg++13.3.0 | Success | 107,845+12.46 RP | ||
| Jan 30, 2026 14:25 | CPPg++13.3.0 | Success | 124,593+80.26 RP | ||
| Jan 27, 2026 08:17 | RUSTrust-1.93.0 | Success | 106,698 | ||
| Jan 27, 2026 08:06 | RUSTrust-1.93.0 | Success | 105,747 | ||
| Jan 27, 2026 07:40 | RUSTrust-1.93.0 | Success | 115,271 | ||
| Jan 21, 2026 06:49 | CPPclang++18.1.3 | Success | 448,595 | ||
| Jan 21, 2026 05:12 | RUSTrust-1.92.0 | Success | 61,160+12.79 RP | ||
| Jan 21, 2026 05:07 | RUSTrust-1.92.0 | Success | 68,041 | ||
| Jan 21, 2026 05:06 | RUSTrust-1.92.0 | Error | |||
| Jan 21, 2026 04:19 | RUSTrust-1.92.0 | Success | 67,162 | ||
| Jan 21, 2026 04:18 | RUSTrust-1.92.0 | Success | 66,352+7.69 RP | ||
| Jan 21, 2026 04:18 | RUSTrust-1.92.0 | Success | 69,921+22.03 RP | ||
| Jan 21, 2026 04:14 | RUSTrust-1.92.0 | Success | 82,653+14.49 RP | ||
| Jan 21, 2026 04:12 | RUSTrust-1.92.0 | Success | 96,597 | ||
| Jan 21, 2026 04:10 | RUSTrust-1.92.0 | Success | 106,678 | ||
| Jan 21, 2026 04:10 | RUSTrust-1.92.0 | Success | 93,903+16.29 RP | ||
| Jan 21, 2026 04:09 | RUSTrust-1.92.0 | Success | 110,867+28.40 RP | ||
| Jan 21, 2026 04:08 | RUSTrust-1.92.0 | Success | 161,810+31.06 RP | ||
| Jan 21, 2026 04:06 | RUSTrust-1.92.0 | Success | 325,319+30.74 RP | ||
| Jan 21, 2026 00:37 | RUSTrust-1.92.0 | Success | 93,217 | ||
| Jan 21, 2026 00:36 | RUSTrust-1.92.0 | Success | 96,393 | ||
| Jan 19, 2026 18:22 | CPPg++13.3.0 | Error | |||
| Jan 17, 2026 04:52 | RUSTrust-1.92.0 | Success | 108,664 | ||
| Jan 17, 2026 04:24 | RUSTrust-1.92.0 | Success | 119,157 | ||
| Jan 17, 2026 04:24 | RUSTrust-1.92.0 | Success | 119,126 | ||
| Jan 14, 2026 05:34 | RUSTrust-1.92.0 | Success | 231,453 | ||
| Jan 14, 2026 05:29 | RUSTrust-1.92.0 | Success | 218,866 | ||
| Jan 14, 2026 02:04 | RUSTrust-1.92.0 | Success | 248,667 | ||
| Jan 14, 2026 02:03 | RUSTrust-1.92.0 | Success | 253,084 | ||
| Jan 14, 2026 01:15 | RUSTrust-1.92.0 | Success | 104,955 | ||
| Jan 14, 2026 01:14 | RUSTrust-1.92.0 | Success | 106,888 | ||
| Jan 14, 2026 01:14 | RUSTrust-1.92.0 | Success | 104,255 | ||
| Jan 14, 2026 01:13 | RUSTrust-1.92.0 | Success | 104,172 | ||
| Jan 14, 2026 01:12 | RUSTrust-1.92.0 | Success | 248,326 | ||
| Jan 14, 2026 01:11 | RUSTrust-1.92.0 | Success | 265,028 | ||
| Jan 14, 2026 01:09 | RUSTrust-1.92.0 | Success | 251,207 | ||
| Jan 14, 2026 00:47 | RUSTrust-1.92.0 | Success | 255,205 | ||
| Jan 11, 2026 11:14 | CPPclang++18.1.3 | Success | 94,905 | ||
| Jan 10, 2026 17:04 | RUSTrust-1.91.1 | Error | |||
| Jan 10, 2026 17:02 | RUSTrust-1.91.1 | Error | |||
| Jan 9, 2026 23:18 | RUSTrust-1.91.1 | Error | |||
| Jan 9, 2026 23:13 | RUSTrust-1.91.1 | Success | 107,798 | ||
| Jan 9, 2026 22:21 | RUSTrust-1.91.1 | Success | 107,840 | ||
| Jan 9, 2026 22:10 | RUSTrust-1.91.1 | Success | 107,140 | ||
| Jan 9, 2026 21:55 | RUSTrust-1.91.1 | Success | 107,240 | ||
| Jan 9, 2026 21:30 | RUSTrust-1.91.1 | Success | 108,110 | ||
| Jan 9, 2026 21:26 | RUSTrust-1.91.1 | Success | 106,724+0.77 RP | ||
| Jan 9, 2026 21:21 | RUSTrust-1.91.1 | Success | 107,912 | ||
| Jan 9, 2026 21:19 | RUSTrust-1.91.1 | Error | |||
| Jan 9, 2026 21:17 | RUSTrust-1.91.1 | Success | 108,519 | ||
| Jan 9, 2026 20:59 | RUSTrust-1.91.1 | Success | 108,797 | ||
| Jan 9, 2026 20:55 | RUSTrust-1.91.1 | Success | 109,069 | ||
| Jan 9, 2026 20:50 | RUSTrust-1.91.1 | Success | 107,607+13.85 RP | ||
| Jan 9, 2026 20:27 | RUSTrust-1.91.1 | Success | 126,447+79.08 RP | ||
| Jan 8, 2026 16:44 | RUSTrust-1.92.0 | Success | 336,009+3.81 RP | ||
| Jan 8, 2026 16:23 | RUSTrust-1.92.0 | Success | 385,322+0.20 RP | ||
| Jan 8, 2026 06:00 | RUSTrust-1.92.0 | Success | 388,264+25.76 RP |