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 21, 2026 02:00

Dominique Garmier

Error

Source Code

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

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	36,069,493	21,464,000	4,304,000	2,117,632	expected "881622654 ", got "0 "
2	Sep 11, 2026 16:11	0	38,058,190	23,461,000	4,315,000	2,117,632	expected "862869826 ", got "0 "
3	Sep 11, 2026 16:11	0	42,214,509	26,908,000	4,313,000	2,117,632	expected "881652983 ", got "0 "
4	Mar 20, 2026 11:21	19,431	25,744,097	9,221,000	2,049,000	2,269,184
5	Mar 20, 2026 11:21	19,500	26,765,857	11,310,000	0	2,289,664
6	Mar 20, 2026 03:04	19,529	32,322,016	10,298,000	1,029,000	2,273,280
7	Mar 20, 2026 03:04	19,597	27,906,137	10,333,000	1,033,000	2,265,088
8	Mar 19, 2026 03:32	19,598	28,086,412	10,334,000	1,033,000	2,289,664
9	Mar 20, 2026 07:45	19,636	31,128,898	10,354,000	1,035,000	2,260,992
10	Mar 19, 2026 12:13	19,672	23,723,143	11,410,000	0	2,277,376
11	Mar 20, 2026 11:37	19,738	27,636,926	10,408,000	1,040,000	2,289,664
12	Mar 20, 2026 07:45	19,743	31,436,675	10,410,000	1,041,000	2,519,040
13	Mar 19, 2026 06:49	19,743	25,434,638	10,410,000	1,041,000	2,265,088
14	Mar 19, 2026 03:49	19,753	27,592,319	10,416,000	1,041,000	2,379,776
15	Mar 19, 2026 12:13	19,759	27,343,916	10,419,000	1,041,000	2,281,472
16	Mar 19, 2026 03:51	19,759	28,896,509	10,419,000	1,041,000	2,289,664
17	Mar 20, 2026 11:21	19,767	32,822,168	10,423,000	1,042,000	2,289,664
18	Mar 19, 2026 06:49	19,771	32,726,854	10,425,000	1,042,000	2,265,088
19	Mar 19, 2026 03:51	19,771	26,549,776	10,425,000	1,042,000	2,289,664
20	Mar 19, 2026 03:28	19,786	32,766,705	10,433,000	1,043,000	2,523,136
21	Mar 20, 2026 11:37	19,797	30,842,467	10,439,000	1,043,000	2,269,184
22	Mar 19, 2026 12:13	19,947	32,763,815	10,518,000	1,051,000	2,506,752
23	Mar 19, 2026 03:49	19,998	33,891,323	10,545,000	1,054,000	2,289,664
24	Mar 19, 2026 03:28	20,052	31,821,721	11,630,000	0	2,260,992
25	Mar 19, 2026 03:28	20,053	29,199,885	11,631,000	0	2,289,664
26	Mar 19, 2026 03:32	20,059	29,947,717	10,577,000	1,057,000	2,273,280
27	Mar 19, 2026 03:32	20,059	28,438,234	10,577,000	1,057,000	2,265,088
28	Mar 19, 2026 03:51	20,081	31,196,338	10,589,000	1,058,000	2,281,472
29	Mar 19, 2026 03:49	20,088	27,691,100	11,651,000	0	2,371,584
30	Mar 20, 2026 11:37	20,095	25,940,799	11,655,000	0	2,289,664
31	Mar 20, 2026 03:04	20,153	32,365,085	10,627,000	1,062,000	2,289,664
32	Mar 21, 2026 02:00	20,155	33,055,895	10,628,000	1,062,000	2,289,664
33	Mar 20, 2026 07:45	20,164	29,807,587	10,632,000	1,063,000	2,289,664
34	Mar 21, 2026 02:00	20,229	48,545,267	11,733,000	0	2,265,088
35	Mar 21, 2026 02:00	20,269	40,969,880	10,688,000	1,068,000	2,260,992
36	Mar 19, 2026 06:49	20,597	27,495,297	10,951,000	995,000	2,265,088

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