Large integer multiplication

Multiply two large unsigned integers as fast as possible.

Input

Exactly 500,000 bytes on STDIN: two unsigned integers encoded back-to-back, each 250,000 bytes, in little-endian byte order.

Output

Write exactly 500,000 bytes to STDOUT containing the product in little-endian byte order.

Restrictions:600s256Mb 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.

Back to listMar 19, 2026 16:43

Dominique GarmierScore: 8,888Success

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Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory
1	Mar 19, 2026 18:38	8,793	44,320,964	15,987,000	5,995,000	2,342,912
2	Mar 19, 2026 11:05	8,798	47,104,843	18,996,000	2,999,000	2,269,184
3	Mar 19, 2026 18:58	8,800	47,328,674	19,000,000	3,000,000	2,269,184
4	Mar 19, 2026 11:46	8,801	51,425,501	19,002,000	3,000,000	2,273,280
5	Mar 19, 2026 18:47	8,807	47,829,807	18,014,000	4,003,000	2,277,376
6	Mar 19, 2026 19:15	8,810	44,978,443	19,023,000	3,003,000	2,273,280
7	Mar 19, 2026 17:33	8,825	49,920,560	19,055,000	3,008,000	2,347,008
8	Mar 19, 2026 11:05	8,830	46,643,471	17,059,000	5,017,000	2,285,568
9	Mar 19, 2026 11:46	8,833	46,570,825	15,057,000	7,026,000	2,277,376
10	Mar 19, 2026 19:15	8,838	45,303,051	17,073,000	5,021,000	2,269,184
11	Mar 19, 2026 11:05	8,843	45,567,813	16,079,000	6,029,000	2,285,568
12	Mar 19, 2026 11:05	8,847	45,336,278	18,097,000	4,021,000	2,285,568
13	Mar 19, 2026 19:03	8,855	48,242,690	18,112,000	4,025,000	2,330,624
14	Mar 19, 2026 11:05	8,855	44,770,671	18,113,000	4,025,000	2,277,376
15	Mar 19, 2026 17:33	8,866	45,096,941	18,136,000	4,030,000	2,367,488
16	Mar 19, 2026 18:47	8,876	47,695,899	18,156,000	4,034,000	2,351,104
17	Mar 19, 2026 11:05	8,876	43,962,711	18,155,000	4,034,000	2,351,104
18	Mar 19, 2026 19:15	8,884	45,061,909	16,154,000	6,057,000	2,482,176
19	Mar 19, 2026 18:38	8,884	46,415,555	16,154,000	6,057,000	2,383,872
20	Mar 19, 2026 11:33	8,885	44,797,602	17,165,000	5,048,000	2,273,280
21	Mar 19, 2026 18:58	8,888	41,520,681	14,141,000	8,080,000	2,396,160
22	Mar 19, 2026 11:05	8,888	46,469,440	17,171,000	5,050,000	2,293,760
23	Mar 19, 2026 11:33	8,896	42,138,206	16,174,000	6,065,000	2,260,992
24	Mar 19, 2026 19:19	8,899	45,598,552	14,158,000	8,090,000	2,260,992
25	Mar 19, 2026 18:38	8,904	50,312,674	18,213,000	4,047,000	2,285,568
26	Mar 19, 2026 11:33	8,932	49,281,888	18,270,000	4,060,000	2,289,664
27	Mar 19, 2026 19:03	8,984	47,725,677	17,355,000	5,104,000	2,277,376
28	Mar 19, 2026 18:47	8,986	42,256,925	18,381,000	4,084,000	2,273,280
29	Mar 19, 2026 11:33	8,997	46,438,353	18,403,000	4,089,000	2,285,568
30	Mar 19, 2026 19:19	9,025	45,701,879	18,461,000	4,102,000	2,490,368
31	Mar 19, 2026 11:05	9,028	45,159,925	18,467,000	4,103,000	2,506,752
32	Mar 19, 2026 19:19	9,032	44,246,066	19,501,000	3,079,000	2,375,680
33	Mar 19, 2026 11:05	9,032	46,622,070	18,476,000	4,105,000	2,502,656
34	Mar 19, 2026 18:58	9,040	55,145,278	18,491,000	4,109,000	2,277,376
35	Mar 19, 2026 17:33	9,075	49,584,452	18,562,000	4,125,000	2,506,752
36	Mar 19, 2026 11:33	9,086	48,495,246	15,801,000	6,913,000	2,269,184
37	Mar 19, 2026 11:46	9,091	54,332,165	21,694,000	1,033,000	2,519,040
38	Mar 19, 2026 16:43	9,108	52,125,230	16,561,000	6,210,000	2,396,160
39	Mar 19, 2026 16:43	9,128	49,989,787	16,866,000	5,953,000	2,277,376
40	Mar 19, 2026 16:43	9,155	48,952,141	18,908,000	3,980,000	2,514,944
41	Mar 19, 2026 11:33	9,216	49,871,440	13,023,000	10,018,000	2,285,568
42	Mar 19, 2026 19:03	9,320	50,592,737	18,234,000	5,065,000	2,478,080

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