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 listDec 28, 2025 20:15

imotw2

Error

Source Code

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

Challenge History

Date	Challenger	Cost	Type	Status
Sep 11, 2026 14:12	Andrew Epstein	10.00	Custom	Solution Broken

Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory	Error
1	Sep 11, 2026 14:16	0	16,948,428	0	6,875,000	20,480	No answer to stdout. Died or killed?
2	Dec 28, 2025 20:12	47,474	48,064,643	23,456,000	4,079,000	2,523,136
3	Dec 28, 2025 20:13	48,716	52,384,051	23,210,000	5,045,000	2,359,296
4	Dec 28, 2025 20:12	48,797	50,760,590	24,259,000	4,043,000	2,461,696
5	Dec 28, 2025 20:12	48,797	48,655,456	23,248,000	5,054,000	2,265,088
6	Dec 28, 2025 20:15	49,128	50,506,198	23,406,000	5,088,000	2,326,528
7	Dec 28, 2025 20:13	49,190	52,299,494	23,436,000	5,094,000	2,469,888
8	Dec 28, 2025 20:13	49,198	46,349,210	24,459,000	4,076,000	2,510,848
9	Dec 28, 2025 20:12	49,267	49,691,917	23,473,000	5,102,000	2,506,752
10	Dec 28, 2025 20:12	49,562	56,586,871	24,640,000	4,106,000	2,506,752
11	Dec 28, 2025 20:13	49,800	57,621,243	24,900,000	3,984,000	2,400,256
12	Dec 28, 2025 20:13	49,819	61,161,947	24,910,000	3,985,000	2,301,952
13	Dec 28, 2025 20:13	49,841	51,869,145	24,921,000	3,987,000	2,396,160
14	Dec 28, 2025 22:56	49,976	61,484,584	23,989,000	4,997,000	2,490,368
15	Dec 28, 2025 22:56	50,055	53,817,574	25,028,000	4,004,000	2,506,752
16	Dec 28, 2025 22:56	50,086	52,443,070	24,042,000	5,008,000	2,318,336
17	Dec 28, 2025 20:42	50,091	52,799,294	25,046,000	4,007,000	2,347,008
18	Dec 28, 2025 20:13	50,229	53,839,211	25,115,000	4,018,000	2,453,504
19	Dec 28, 2025 22:56	50,557	52,897,073	25,279,000	4,044,000	2,494,464
20	Dec 28, 2025 20:12	50,591	51,899,899	25,296,000	4,047,000	2,338,816
21	Dec 28, 2025 20:13	50,952	55,928,109	24,457,000	5,095,000	2,310,144
22	Dec 28, 2025 20:12	50,962	53,273,845	24,462,000	5,096,000	2,269,184
23	Dec 28, 2025 20:42	51,053	55,847,997	24,506,000	5,105,000	2,445,312
24	Dec 28, 2025 20:12	51,519	59,216,353	24,901,000	4,980,000	2,457,600
25	Dec 28, 2025 20:13	51,590	53,649,836	26,827,000	3,095,000	2,281,472
26	Dec 28, 2025 20:12	51,779	56,371,941	26,028,000	4,004,000	2,367,488
27	Dec 28, 2025 20:15	52,102	51,666,908	25,183,000	5,036,000	2,265,088
28	Dec 28, 2025 22:56	52,367	52,620,190	24,299,000	6,074,000	2,273,280
29	Dec 28, 2025 20:15	52,429	56,078,986	26,355,000	4,054,000	2,502,656
30	Dec 28, 2025 22:56	52,772	60,659,448	24,487,000	6,121,000	2,310,144
31	Dec 28, 2025 20:42	53,014	57,949,227	25,624,000	5,124,000	2,424,832

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