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.

Restrictions:30s256Mb 1 Score Packages

Feel free to create an issue if you need an extra library from the standard Ubuntu repository.

Name	Version	Description
libc6-dev	2.39-0ubuntu8.7	GNU C Library: Development Libraries and Header Files Contains the symlinks, headers, and object files needed to compile and link programs which use the standard C library.
libclang-common-14-dev	1:14.0.6-19build4	Clang library - Common development package Clang project is a C, C++, Objective C and Objective C++ front-end based on the LLVM compiler. Its goal is to offer a replacement to the GNU Compiler Collection (GCC). . Clang implements all of the ISO C++ 1998, 11, 14 and 17 standards and also provides most of the support of C++20. . This package contains the Clang generic headers.
libclang-common-15-dev	1:15.0.7-14build3	Clang library - Common development package Clang project is a C, C++, Objective C and Objective C++ front-end based on the LLVM compiler. Its goal is to offer a replacement to the GNU Compiler Collection (GCC). . Clang implements all of the ISO C++ 1998, 11, 14 and 17 standards and also provides most of the support of C++20. . This package contains the Clang generic headers.
libclang-common-16-dev	1:16.0.6-23ubuntu4	Clang library - Common development package Clang project is a C, C++, Objective C and Objective C++ front-end based on the LLVM compiler. Its goal is to offer a replacement to the GNU Compiler Collection (GCC). . Clang implements all of the ISO C++ 1998, 11, 14 and 17 standards and also provides most of the support of C++20. . This package contains the Clang generic headers.
libclang-common-17-dev	1:17.0.6-9ubuntu1	Clang library - Common development package Clang project is a C, C++, Objective C and Objective C++ front-end based on the LLVM compiler. Its goal is to offer a replacement to the GNU Compiler Collection (GCC). . Clang implements all of the ISO C++ 1998, 11, 14 and 17 standards and also provides most of the support of C++20. . This package contains the Clang generic headers.
libclang-common-18-dev	1:18.1.3-1ubuntu1	Clang library - Common development package Clang project is a C, C++, Objective C and Objective C++ front-end based on the LLVM compiler. Its goal is to offer a replacement to the GNU Compiler Collection (GCC). . Clang implements all of the ISO C++ 1998, 11, 14 and 17 standards and also provides most of the support of C++20. . This package contains the Clang generic headers.
libclang-common-19-dev	1:19.1.1-1ubuntu1~24.04.2	Clang library - Common development package Clang project is a C, C++, Objective C and Objective C++ front-end based on the LLVM compiler. Its goal is to offer a replacement to the GNU Compiler Collection (GCC). . Clang implements all of the ISO C++ 1998, 11, 14 and 17 standards and also provides most of the support of C++20. . This package contains the Clang generic headers.
libclang-common-20-dev	1:20.1.2-0ubuntu1~24.04.3	Clang library - Common development package Clang project is a C, C++, Objective C and Objective C++ front-end based on the LLVM compiler. Its goal is to offer a replacement to the GNU Compiler Collection (GCC). . Clang implements all of the ISO C++ 1998, 11, 14 and 17 standards and also provides most of the support of C++20. . This package contains the Clang generic headers.
libcrypt-dev	1:4.4.36-4build1	libcrypt development files This package contains the files needed for developing applications that use libcrypt.
libgcc-10-dev	10.5.0-4ubuntu2.1	GCC support library (development files) This package contains the headers and static library files necessary for building C programs which use libgcc, libgomp, libquadmath, libssp or libitm.
libgcc-11-dev	11.5.0-1ubuntu1~24.04.1	GCC support library (development files) This package contains the headers and static library files necessary for building C programs which use libgcc, libgomp, libquadmath, libssp or libitm.
libgcc-12-dev	12.4.0-2ubuntu1~24.04.1	GCC support library (development files) This package contains the headers and static library files necessary for building C programs which use libgcc, libgomp, libquadmath, libssp or libitm.
libgcc-13-dev	13.3.0-6ubuntu2~24.04.1	GCC support library (development files) This package contains the headers and static library files necessary for building C programs which use libgcc, libgomp, libquadmath, libssp or libitm.
libgcc-14-dev	14.2.0-4ubuntu2~24.04.1	GCC support library (development files) This package contains the headers and static library files necessary for building C programs which use libgcc, libgomp, libquadmath, libssp or libitm.
libobjc-13-dev	13.3.0-6ubuntu2~24.04.1	Runtime library for GNU Objective-C applications (development files) This package contains the headers and static library files needed to build GNU ObjC applications.
libssl-dev	3.0.13-0ubuntu3.11	Secure Sockets Layer toolkit - development files This package is part of the OpenSSL project's implementation of the SSL and TLS cryptographic protocols for secure communication over the Internet. . It contains development libraries, header files, and manpages for libssl and libcrypto.
libstdc++-10-dev	10.5.0-4ubuntu2.1	GNU Standard C++ Library v3 (development files) This package contains the headers and static library files necessary for building C++ programs which use libstdc++. . libstdc++-v3 is a complete rewrite from the previous libstdc++-v2, which was included up to g++-2.95. The first version of libstdc++-v3 appeared in g++-3.0.
libstdc++-11-dev	11.5.0-1ubuntu1~24.04.1	GNU Standard C++ Library v3 (development files) This package contains the headers and static library files necessary for building C++ programs which use libstdc++. . libstdc++-v3 is a complete rewrite from the previous libstdc++-v2, which was included up to g++-2.95. The first version of libstdc++-v3 appeared in g++-3.0.
libstdc++-12-dev	12.4.0-2ubuntu1~24.04.1	GNU Standard C++ Library v3 (development files) This package contains the headers and static library files necessary for building C++ programs which use libstdc++. . libstdc++-v3 is a complete rewrite from the previous libstdc++-v2, which was included up to g++-2.95. The first version of libstdc++-v3 appeared in g++-3.0.
libstdc++-13-dev	13.3.0-6ubuntu2~24.04.1	GNU Standard C++ Library v3 (development files) This package contains the headers and static library files necessary for building C++ programs which use libstdc++. . libstdc++-v3 is a complete rewrite from the previous libstdc++-v2, which was included up to g++-2.95. The first version of libstdc++-v3 appeared in g++-3.0.
libstdc++-14-dev	14.2.0-4ubuntu2~24.04.1	GNU Standard C++ Library v3 (development files) This package contains the headers and static library files necessary for building C++ programs which use libstdc++. . libstdc++-v3 is a complete rewrite from the previous libstdc++-v2, which was included up to g++-2.95. The first version of libstdc++-v3 appeared in g++-3.0.
libtbb-dev	2021.11.0-2ubuntu2	parallelism library for C++ - development files TBB is a library that helps you leverage multi-core processor performance without having to be a threading expert. It represents a higher-level, task-based parallelism that abstracts platform details and threading mechanism for performance and scalability. . (Note: if you are a user of the i386 architecture, i.e., 32-bit Intel or compatible hardware, this package only supports Pentium4-compatible and higher processors.) . This package includes the TBB development files.

Back to listMar 2, 2026 21:26

JuneL

Error

Source Code

Source code access is restricted. Log in to request access.

Challenge History

Date	Challenger	Cost	Type	Status
Oct 5, 2026 19:28	Andrew Epstein	10.00	Custom	Solution Broken

Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory	Error
1	Oct 5, 2026 19:34	0	18,261,392	0	7,907,000	28,672	No answer to stdout. Died or killed?	stderr
2	Mar 2, 2026 21:26	67,378	64,117,765	33,067,000	6,012,000	2,371,584
3	Mar 2, 2026 21:13	67,481	72,192,122	33,118,000	6,021,000	2,461,696
4	Mar 2, 2026 21:13	68,133	67,003,486	33,438,000	6,079,000	2,338,816
5	Mar 2, 2026 21:26	68,171	67,337,116	35,484,000	4,055,000	2,314,240
6	Mar 2, 2026 21:26	68,321	65,855,728	33,530,000	6,096,000	2,453,504
7	Mar 2, 2026 21:26	68,384	69,772,360	34,578,000	5,085,000	2,347,008
8	Mar 2, 2026 21:13	69,348	66,374,784	36,200,000	4,022,000	2,375,680
9	Mar 2, 2026 21:26	69,548	70,155,885	36,305,000	4,033,000	2,424,832
10	Mar 2, 2026 21:13	70,124	68,632,361	34,572,000	6,100,000	2,531,328
11	Mar 2, 2026 21:13	70,484	67,826,792	33,902,000	6,979,000	2,482,176
12	Mar 2, 2026 21:12	71,103	66,682,531	36,211,000	5,029,000	2,347,008
13	Mar 2, 2026 21:13	71,366	66,767,856	36,345,000	5,047,000	2,314,240
14	Mar 2, 2026 21:12	71,428	66,378,108	36,376,000	5,052,000	2,412,544
15	Mar 2, 2026 21:26	71,521	66,673,876	35,412,000	6,070,000	2,371,584
16	Mar 2, 2026 21:13	71,655	68,943,749	35,478,000	6,082,000	2,502,656
17	Mar 2, 2026 21:26	72,567	70,476,994	37,079,000	5,010,000	2,502,656
18	Mar 2, 2026 21:12	73,224	76,814,980	36,403,000	6,067,000	2,408,448
19	Mar 2, 2026 21:26	73,343	70,525,467	37,475,000	5,064,000	2,478,080
20	Mar 2, 2026 21:12	74,098	71,857,093	36,981,000	5,996,000	2,387,968
21	Mar 2, 2026 21:13	74,269	70,783,769	38,068,000	5,008,000	2,514,944
22	Mar 2, 2026 21:12	74,397	76,043,753	37,129,000	6,021,000	2,449,408
23	Mar 2, 2026 21:26	74,516	69,430,884	37,189,000	6,030,000	2,330,624
24	Mar 2, 2026 21:12	75,083	67,260,495	38,485,000	5,063,000	2,355,200
25	Mar 2, 2026 21:26	75,188	69,307,900	37,524,000	6,085,000	2,510,848
26	Mar 2, 2026 21:26	75,790	72,260,978	37,964,000	5,994,000	2,342,912
27	Mar 2, 2026 21:12	76,393	69,378,866	38,266,000	6,042,000	2,396,160
28	Mar 2, 2026 21:26	77,414	78,692,565	38,914,000	5,986,000	2,301,952
29	Mar 2, 2026 21:12	78,178	79,059,451	39,298,000	6,045,000	2,318,336
30	Mar 2, 2026 21:12	79,112	69,943,639	37,905,000	7,980,000	2,387,968
31	Mar 2, 2026 21:26	79,669	74,297,761	40,181,000	6,027,000	2,293,760
32	Mar 2, 2026 21:26	80,998	75,609,637	40,982,000	5,997,000	2,478,080
33	Mar 2, 2026 21:13	83,803	75,792,105	42,531,000	6,075,000	2,473,984
34	Mar 2, 2026 21:26	86,233	74,406,068	45,014,000	5,001,000	2,502,656

Model	Intel(R) Xeon(R) CPU E3-1271 v3 @ 3.60GHz
Cores	1