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 20, 2026 14:44

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 16:11	0	37,748,085	23,268,000	4,137,000	2,117,632	expected "857903235 ", got "0 "
2	Sep 11, 2026 16:11	0	40,075,937	24,736,000	4,270,000	2,117,632	expected "867809186 ", got "0 "
3	Sep 11, 2026 16:11	0	46,754,079	31,033,000	4,599,000	2,117,632	expected "885547400 ", got "0 "
4	Mar 20, 2026 13:32	18,814	31,200,404	8,928,000	1,984,000	2,281,472
5	Mar 20, 2026 14:06	18,824	28,650,239	8,933,000	1,985,000	2,260,992
6	Mar 20, 2026 12:43	18,852	30,151,586	8,946,000	1,988,000	2,281,472
7	Mar 20, 2026 13:32	18,914	29,230,596	8,976,000	1,994,000	2,285,568
8	Mar 20, 2026 13:02	18,966	27,850,353	10,000,000	1,000,000	2,289,664
9	Mar 20, 2026 13:02	18,967	25,691,503	9,001,000	2,000,000	2,289,664
10	Mar 20, 2026 13:40	18,991	28,056,954	9,013,000	2,002,000	2,289,664
11	Mar 20, 2026 13:40	19,003	31,773,632	9,018,000	2,004,000	2,285,568
12	Mar 20, 2026 13:02	19,033	29,179,193	10,036,000	1,003,000	2,289,664
13	Mar 20, 2026 12:58	19,072	27,912,680	9,051,000	2,011,000	2,269,184
14	Mar 20, 2026 12:15	19,124	26,674,818	9,076,000	2,016,000	2,269,184
15	Mar 20, 2026 12:58	19,131	30,826,919	9,079,000	2,017,000	2,289,664
16	Mar 20, 2026 12:05	19,145	32,641,582	10,095,000	1,009,000	2,269,184
17	Mar 20, 2026 14:06	19,166	28,648,460	10,106,000	1,010,000	2,260,992
18	Mar 20, 2026 12:05	19,169	31,294,500	9,097,000	2,021,000	2,265,088
19	Mar 20, 2026 14:06	19,188	30,135,934	9,106,000	2,023,000	2,289,664
20	Mar 20, 2026 14:44	19,198	27,868,350	9,111,000	2,024,000	2,281,472
21	Mar 20, 2026 12:43	19,203	27,387,815	10,126,000	1,012,000	2,359,296
22	Mar 20, 2026 12:27	19,269	28,800,601	9,144,000	2,032,000	2,527,232
23	Mar 20, 2026 13:32	19,279	28,786,980	9,149,000	2,033,000	2,289,664
24	Mar 20, 2026 12:15	19,291	27,003,087	9,155,000	2,034,000	2,289,664
25	Mar 20, 2026 12:15	19,312	25,953,646	9,165,000	2,036,000	2,285,568
26	Mar 20, 2026 12:27	19,328	27,230,415	9,172,000	2,038,000	2,285,568
27	Mar 20, 2026 13:40	19,345	34,067,461	9,180,000	2,040,000	2,273,280
28	Mar 20, 2026 12:05	19,484	29,753,788	9,247,000	2,054,000	2,269,184
29	Mar 20, 2026 12:58	19,528	30,353,671	10,297,000	1,029,000	2,514,944
30	Mar 20, 2026 12:43	19,831	35,858,297	9,411,000	2,091,000	2,269,184
31	Mar 20, 2026 14:44	19,847	28,379,320	10,465,000	1,046,000	2,289,664
32	Mar 20, 2026 14:44	19,914	31,880,398	10,500,000	1,050,000	2,523,136
33	Mar 20, 2026 12:27	19,971	28,414,758	10,530,000	1,053,000	2,277,376

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