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 listSep 29, 2025 19:55

Wookyung Jeong

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Challenge History

Date	Challenger	Cost	Type	Status
Oct 5, 2026 19:28	Andrew Epstein	10.00	Custom	Solution Broken

Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory	Error
1	Oct 5, 2026 19:32	0	32,571,719	21,008,000	1,101,000	16,384	No answer to stdout. Died or killed?
2	Sep 29, 2025 19:52	51,507	56,778,939	26,887,000	2,987,000	2,289,664
3	Sep 29, 2025 20:00	51,510	56,795,479	25,893,000	3,983,000	2,306,048
4	Sep 29, 2025 19:59	51,698	52,073,040	27,986,000	1,999,000	2,322,432
5	Sep 29, 2025 20:00	51,943	56,844,772	28,119,000	2,008,000	2,449,408
6	Sep 29, 2025 19:59	52,131	57,279,456	28,221,000	2,015,000	2,486,272
7	Sep 29, 2025 20:00	52,303	52,930,050	28,314,000	2,022,000	2,519,040
8	Sep 29, 2025 20:00	52,405	53,803,653	28,369,000	2,026,000	2,404,352
9	Sep 29, 2025 19:52	52,553	51,535,412	28,449,000	2,032,000	2,334,720
10	Sep 29, 2025 19:59	52,659	52,642,079	28,506,000	2,036,000	2,318,336
11	Sep 29, 2025 19:59	52,955	56,782,339	29,691,000	1,023,000	2,400,256
12	Sep 29, 2025 20:00	53,260	57,784,248	27,902,000	2,989,000	2,457,600
13	Sep 29, 2025 19:52	53,434	54,873,903	27,993,000	2,999,000	2,289,664
14	Sep 29, 2025 19:52	53,498	59,048,357	29,028,000	2,001,000	2,473,984
15	Sep 29, 2025 20:00	53,641	60,068,011	29,105,000	2,007,000	2,449,408
16	Sep 29, 2025 19:59	53,703	55,567,855	29,139,000	2,009,000	2,465,792
17	Sep 29, 2025 19:59	53,921	52,329,151	30,266,000	1,008,000	2,502,656
18	Sep 29, 2025 20:00	53,998	56,904,136	29,299,000	2,020,000	2,322,432
19	Sep 29, 2025 19:53	54,388	58,252,738	28,493,000	3,052,000	2,461,696
20	Sep 29, 2025 19:59	54,955	56,513,225	26,894,000	4,980,000	2,285,568
21	Sep 29, 2025 19:53	54,957	60,663,511	29,883,000	1,992,000	2,482,176
22	Sep 29, 2025 19:52	54,990	62,686,230	29,901,000	1,993,000	2,424,832
23	Sep 29, 2025 19:55	55,290	58,777,546	28,060,000	4,008,000	2,502,656
24	Sep 29, 2025 20:00	55,438	58,360,140	30,145,000	2,009,000	2,326,528
25	Sep 29, 2025 19:52	55,624	52,598,289	29,238,000	3,024,000	2,359,296
26	Sep 29, 2025 19:59	55,824	56,563,646	28,331,000	4,047,000	2,433,024
27	Sep 29, 2025 19:52	55,957	55,245,270	30,427,000	2,028,000	2,428,928
28	Sep 29, 2025 20:00	56,309	61,985,275	29,598,000	3,061,000	2,416,640
29	Sep 29, 2025 19:59	56,341	64,605,079	28,594,000	4,084,000	2,437,120
30	Sep 29, 2025 19:53	56,366	58,266,422	30,649,000	2,043,000	2,506,752
31	Sep 29, 2025 19:59	56,672	58,465,348	29,882,000	2,988,000	2,404,352
32	Sep 29, 2025 19:55	56,721	57,989,188	29,908,000	2,990,000	2,400,256
33	Sep 29, 2025 19:52	56,955	57,518,472	30,031,000	3,003,000	2,490,368
34	Sep 29, 2025 19:59	58,169	59,442,703	30,671,000	3,067,000	2,461,696
35	Sep 29, 2025 19:52	58,416	59,902,282	32,885,000	996,000	2,490,368
36	Sep 29, 2025 19:59	58,771	57,196,231	30,077,000	4,010,000	2,375,680
37	Sep 29, 2025 19:55	59,736	58,457,574	32,609,000	2,038,000	2,428,928

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