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 08:57

Dominique GarmierScore: 8,898Success

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Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory
1	Mar 19, 2026 08:47	8,795	42,267,168	15,991,000	5,996,000	2,314,240
2	Mar 19, 2026 09:03	8,798	45,566,158	17,997,000	3,999,000	2,342,912
3	Mar 19, 2026 08:44	8,811	46,136,883	18,023,000	4,005,000	2,301,952
4	Mar 19, 2026 09:03	8,818	46,638,532	18,037,000	4,008,000	2,289,664
5	Mar 19, 2026 08:57	8,819	45,400,307	18,040,000	4,008,000	2,273,280
6	Mar 19, 2026 08:47	8,819	50,504,330	16,035,000	6,013,000	2,269,184
7	Mar 19, 2026 08:47	8,819	48,129,595	19,042,000	3,006,000	2,285,568
8	Mar 19, 2026 08:52	8,828	50,937,066	18,057,000	4,012,000	2,273,280
9	Mar 19, 2026 09:03	8,828	48,656,926	18,058,000	4,013,000	2,469,888
10	Mar 19, 2026 08:46	8,829	51,234,367	18,059,000	4,013,000	2,277,376
11	Mar 19, 2026 08:47	8,831	47,620,928	15,053,000	7,024,000	2,301,952
12	Mar 19, 2026 08:49	8,835	48,535,605	17,068,000	5,020,000	2,297,856
13	Mar 19, 2026 08:52	8,838	47,125,010	19,082,000	3,013,000	2,314,240
14	Mar 19, 2026 09:03	8,843	47,789,984	19,094,000	3,014,000	2,416,640
15	Mar 19, 2026 08:46	8,869	42,827,294	19,149,000	3,023,000	2,289,664
16	Mar 19, 2026 08:47	8,874	49,493,589	15,126,000	7,059,000	2,277,376
17	Mar 19, 2026 08:52	8,882	46,322,183	16,149,000	6,055,000	2,277,376
18	Mar 19, 2026 09:03	8,892	45,245,418	19,198,000	3,031,000	2,379,776
19	Mar 19, 2026 09:03	8,895	47,732,788	19,205,000	3,032,000	2,285,568
20	Mar 19, 2026 08:44	8,898	44,945,950	14,156,000	8,089,000	2,285,568
21	Mar 19, 2026 08:49	8,901	53,168,275	17,196,000	5,057,000	2,277,376
22	Mar 19, 2026 09:03	8,902	41,577,677	17,197,000	5,057,000	2,396,160
23	Mar 19, 2026 08:52	8,903	45,345,650	16,188,000	6,070,000	2,506,752
24	Mar 19, 2026 08:52	8,903	49,661,070	20,235,000	2,023,000	2,338,816
25	Mar 19, 2026 08:47	8,906	50,027,612	14,168,000	8,096,000	2,265,088
26	Mar 19, 2026 09:03	8,975	49,097,732	19,378,000	3,059,000	2,285,568
27	Mar 19, 2026 08:57	8,986	43,950,738	16,339,000	6,127,000	2,351,104
28	Mar 19, 2026 08:47	9,008	49,821,104	18,425,000	4,094,000	2,260,992
29	Mar 19, 2026 08:52	9,017	44,910,929	18,444,000	4,098,000	2,371,584
30	Mar 19, 2026 08:47	9,035	48,458,813	15,401,000	7,187,000	2,519,040
31	Mar 19, 2026 08:52	9,038	46,539,199	20,542,000	2,054,000	2,265,088
32	Mar 19, 2026 08:52	9,063	46,626,123	18,538,000	4,119,000	2,322,432
33	Mar 19, 2026 08:57	9,094	51,874,723	19,636,000	3,100,000	2,289,664
34	Mar 19, 2026 08:52	9,128	45,746,016	18,852,000	3,968,000	2,273,280
35	Mar 19, 2026 08:49	9,134	47,672,365	18,863,000	3,971,000	2,265,088
36	Mar 19, 2026 08:46	9,154	51,650,508	17,910,000	4,975,000	2,375,680
37	Mar 19, 2026 08:47	9,158	51,273,217	19,909,000	2,986,000	2,277,376
38	Mar 19, 2026 09:03	9,159	47,301,476	16,925,000	5,973,000	2,260,992
39	Mar 19, 2026 08:44	9,162	49,907,341	18,921,000	3,983,000	2,285,568

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