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.

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Challenge History

Date	Challenger	Cost	Type	Status
Oct 5, 2026 18:59	Andrew Epstein	10.00	Custom	Solution Broken

Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory	Error
1	Oct 5, 2026 19:04	0	17,045,458	0	6,815,000	20,480	No answer to stdout. Died or killed?
2	Dec 28, 2025 18:14	64,176	59,803,150	33,198,000	4,024,000	2,322,432
3	Dec 28, 2025 18:18	64,281	65,128,327	33,253,000	4,030,000	2,424,832
4	Dec 28, 2025 18:22	65,326	64,113,848	32,904,000	4,985,000	2,453,504
5	Dec 28, 2025 18:14	65,416	62,478,700	32,949,000	4,992,000	2,469,888
6	Dec 28, 2025 18:22	65,784	64,215,407	33,135,000	5,020,000	2,519,040
7	Dec 28, 2025 18:18	66,183	65,696,118	32,325,000	6,061,000	2,420,736
8	Dec 28, 2025 18:22	66,391	62,164,434	33,441,000	5,066,000	2,293,760
9	Dec 28, 2025 18:14	66,767	68,759,320	35,668,000	3,057,000	2,379,776
10	Dec 28, 2025 18:18	66,802	66,289,673	32,628,000	6,117,000	2,392,064
11	Dec 28, 2025 18:18	66,986	64,147,017	33,871,000	4,981,000	2,293,760
12	Dec 28, 2025 18:18	67,052	66,615,035	34,902,000	3,988,000	2,506,752
13	Dec 28, 2025 18:14	67,078	67,225,069	32,920,000	5,985,000	2,301,952
14	Dec 28, 2025 18:18	67,209	69,533,370	34,983,000	3,998,000	2,519,040
15	Dec 28, 2025 18:14	67,283	64,524,875	35,022,000	4,002,000	2,334,720
16	Dec 28, 2025 18:27	67,421	65,437,085	34,091,000	5,013,000	2,506,752
17	Dec 28, 2025 18:22	67,572	60,457,987	35,173,000	4,019,000	2,437,120
18	Dec 28, 2025 18:14	67,709	60,542,233	34,237,000	5,034,000	2,433,024
19	Dec 28, 2025 18:14	67,714	65,206,154	34,239,000	5,035,000	2,490,368
20	Dec 28, 2025 18:22	67,902	64,037,251	34,334,000	5,049,000	2,416,640
21	Dec 28, 2025 18:14	68,119	65,906,091	35,457,000	4,052,000	2,445,312
22	Dec 28, 2025 18:22	68,140	61,318,990	33,441,000	6,080,000	2,379,776
23	Dec 28, 2025 18:18	68,159	61,364,943	34,464,000	5,068,000	2,387,968
24	Dec 28, 2025 18:22	68,448	66,505,156	34,611,000	5,089,000	2,347,008
25	Dec 28, 2025 18:27	68,459	64,729,220	34,616,000	5,090,000	2,494,464
26	Dec 28, 2025 18:27	68,491	65,765,077	34,632,000	5,093,000	2,306,048
27	Dec 28, 2025 18:18	68,662	64,402,366	34,846,000	4,978,000	2,330,624
28	Dec 28, 2025 18:22	68,886	67,338,215	33,961,000	5,993,000	2,351,104
29	Dec 28, 2025 18:14	69,488	63,877,804	34,258,000	6,045,000	2,433,024
30	Dec 28, 2025 18:18	69,562	62,839,699	35,303,000	5,043,000	2,334,720
31	Dec 28, 2025 18:22	69,922	68,870,235	35,486,000	5,069,000	2,424,832

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