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	1:20.1.2-0ubuntu1~24.04.2	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.
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	3.0.13-0ubuntu3.9	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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Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory
1	Feb 10, 2026 13:29	79,881	75,341,839	45,324,000	1,007,000	2,371,584
2	Feb 10, 2026 13:58	80,003	68,804,695	46,402,000	0	2,478,080
3	Feb 10, 2026 14:07	80,047	68,085,701	45,418,000	1,009,000	2,523,136
4	Feb 10, 2026 13:29	80,116	68,903,611	45,457,000	1,010,000	2,281,472
5	Feb 10, 2026 14:13	80,148	69,195,270	45,476,000	1,010,000	2,514,944
6	Feb 10, 2026 13:44	80,148	72,476,333	46,486,000	0	2,314,240
7	Feb 10, 2026 13:44	80,183	67,663,126	45,495,000	1,011,000	2,281,472
8	Feb 10, 2026 13:36	80,203	74,865,173	45,507,000	1,011,000	2,269,184
9	Feb 10, 2026 13:36	80,250	70,389,782	45,534,000	1,011,000	2,494,464
10	Feb 10, 2026 14:13	80,266	66,729,658	45,542,000	1,012,000	2,301,952
11	Feb 10, 2026 14:13	80,302	69,209,725	46,575,000	0	2,301,952
12	Feb 10, 2026 13:35	80,321	68,033,425	45,574,000	1,012,000	2,306,048
13	Feb 10, 2026 13:29	80,353	72,449,012	45,592,000	1,013,000	2,281,472
14	Feb 10, 2026 13:58	80,386	79,266,094	46,624,000	0	2,306,048
15	Feb 10, 2026 14:07	80,416	73,407,494	45,628,000	1,013,000	2,510,848
16	Feb 10, 2026 13:36	80,419	78,097,154	46,643,000	0	2,510,848
17	Feb 10, 2026 13:58	80,474	72,073,631	45,661,000	1,014,000	2,273,280
18	Feb 10, 2026 14:04	80,478	71,242,804	46,677,000	0	2,297,856
19	Feb 10, 2026 13:36	80,507	73,004,575	45,679,000	1,015,000	2,306,048
20	Feb 10, 2026 13:58	80,848	75,021,604	44,897,000	1,995,000	2,478,080
21	Feb 10, 2026 14:04	80,850	79,558,679	45,896,000	997,000	2,510,848
22	Feb 10, 2026 14:10	80,850	74,313,998	44,898,000	1,995,000	2,281,472
23	Feb 10, 2026 14:10	80,850	69,654,054	44,898,000	1,995,000	2,490,368
24	Feb 10, 2026 13:58	80,860	74,548,026	46,899,000	0	2,527,232
25	Feb 10, 2026 13:36	80,893	71,378,097	44,922,000	1,996,000	2,306,048
26	Feb 10, 2026 13:36	81,053	71,433,054	46,011,000	1,000,000	2,297,856
27	Feb 10, 2026 14:04	81,072	75,380,853	45,022,000	2,000,000	2,281,472
28	Feb 10, 2026 13:58	81,090	76,671,587	46,032,000	1,000,000	2,293,760
29	Feb 10, 2026 13:35	81,148	72,954,034	46,065,000	1,001,000	2,408,448
30	Feb 10, 2026 14:07	81,150	75,529,262	47,067,000	0	2,310,144
31	Feb 10, 2026 13:44	81,190	69,674,790	46,089,000	1,001,000	2,310,144
32	Feb 10, 2026 13:35	81,238	74,409,407	46,116,000	1,002,000	2,310,144
33	Feb 10, 2026 14:10	81,326	74,764,696	45,162,000	2,007,000	2,301,952

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