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 19, 2026 12:15

Dominique Garmier

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Challenge History

Date	Challenger	Cost	Type	Status
Sep 11, 2026 16:04	Andrew Epstein	10.00	Custom	Solution Broken

Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory	Error
1	Sep 11, 2026 16:10	0	23,422,296	8,160,000	4,299,000	16,384	No answer to stdout. Died or killed?
2	Mar 19, 2026 12:56	17,497	26,901,023	8,119,000	2,029,000	2,281,472
3	Mar 19, 2026 12:56	17,695	26,164,233	8,211,000	2,052,000	2,289,664
4	Mar 19, 2026 13:19	17,712	27,044,995	9,246,000	1,027,000	2,277,376
5	Mar 19, 2026 12:37	17,729	30,801,828	10,283,000	0	2,269,184
6	Mar 19, 2026 13:19	17,745	28,774,546	10,292,000	0	2,277,376
7	Mar 19, 2026 12:51	17,759	26,867,889	9,270,000	1,030,000	2,285,568
8	Mar 19, 2026 12:51	17,764	28,325,859	10,303,000	0	2,289,664
9	Mar 19, 2026 12:15	17,767	27,442,373	10,305,000	0	2,273,280
10	Mar 19, 2026 13:30	17,769	27,226,269	10,306,000	0	2,281,472
11	Mar 19, 2026 12:13	17,778	27,764,162	9,280,000	1,031,000	2,531,328
12	Mar 19, 2026 12:13	17,778	26,333,576	9,280,000	1,031,000	2,285,568
13	Mar 19, 2026 12:59	17,783	28,738,201	9,283,000	1,031,000	2,289,664
14	Mar 19, 2026 12:59	17,797	27,129,505	10,322,000	0	2,285,568
15	Mar 19, 2026 12:13	17,814	25,085,727	9,299,000	1,033,000	2,273,280
16	Mar 19, 2026 12:44	17,831	25,825,602	9,308,000	1,034,000	2,289,664
17	Mar 19, 2026 12:56	17,834	30,871,317	10,344,000	0	2,273,280
18	Mar 19, 2026 13:30	17,836	28,115,197	9,311,000	1,034,000	2,289,664
19	Mar 19, 2026 12:44	17,888	27,442,444	10,375,000	0	2,273,280
20	Mar 19, 2026 13:04	17,900	30,158,154	9,344,000	1,038,000	2,277,376
21	Mar 19, 2026 13:30	17,905	26,340,959	9,347,000	1,038,000	2,289,664
22	Mar 19, 2026 12:17	17,919	31,881,393	10,393,000	0	2,273,280
23	Mar 19, 2026 13:19	17,921	31,121,837	9,355,000	1,039,000	2,277,376
24	Mar 19, 2026 12:17	17,934	29,092,635	9,362,000	1,040,000	2,277,376
25	Mar 19, 2026 12:37	18,010	27,851,287	9,402,000	1,044,000	2,387,968
26	Mar 19, 2026 13:04	18,031	29,146,459	9,413,000	1,045,000	2,273,280
27	Mar 19, 2026 12:59	18,062	28,180,290	9,429,000	1,047,000	2,281,472
28	Mar 19, 2026 12:17	18,062	33,133,339	9,429,000	1,047,000	2,269,184
29	Mar 19, 2026 12:37	18,086	29,883,604	9,441,000	1,049,000	2,281,472
30	Mar 19, 2026 13:04	18,117	30,865,132	9,458,000	1,050,000	2,289,664
31	Mar 19, 2026 12:15	18,183	24,640,858	9,492,000	1,054,000	2,289,664
32	Mar 19, 2026 12:51	18,238	28,291,200	9,521,000	1,057,000	2,523,136
33	Mar 19, 2026 12:44	18,288	30,224,809	9,547,000	1,060,000	2,273,280
34	Mar 19, 2026 12:15	18,483	33,609,829	9,648,000	1,072,000	2,277,376

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