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 08:42

Dominique GarmierScore: 9,015Success

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Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory
1	Mar 19, 2026 08:38	8,924	50,176,711	19,268,000	3,042,000	2,310,144
2	Mar 19, 2026 08:42	8,935	48,058,948	19,291,000	3,046,000	2,273,280
3	Mar 19, 2026 08:02	8,936	50,376,558	17,264,000	5,077,000	2,293,760
4	Mar 19, 2026 08:02	8,938	46,169,328	18,283,000	4,062,000	2,306,048
5	Mar 19, 2026 08:02	8,943	46,074,290	19,309,000	3,048,000	2,281,472
6	Mar 19, 2026 08:20	8,943	49,390,452	16,525,000	5,832,000	2,342,912
7	Mar 19, 2026 08:02	8,946	44,912,286	18,299,000	4,066,000	2,281,472
8	Mar 19, 2026 08:18	8,948	46,848,459	19,321,000	3,050,000	2,277,376
9	Mar 19, 2026 08:38	8,949	44,760,491	19,322,000	3,050,000	2,359,296
10	Mar 19, 2026 08:18	8,950	48,458,269	18,308,000	4,068,000	2,281,472
11	Mar 19, 2026 08:18	8,953	46,107,266	19,331,000	3,052,000	2,293,760
12	Mar 19, 2026 08:02	8,964	45,614,674	19,355,000	3,056,000	2,289,664
13	Mar 19, 2026 08:02	8,966	50,288,736	19,360,000	3,056,000	2,265,088
14	Mar 19, 2026 08:18	8,971	42,807,540	16,311,000	6,116,000	2,289,664
15	Mar 19, 2026 08:38	8,973	51,034,263	17,335,000	5,098,000	2,273,280
16	Mar 19, 2026 08:04	8,975	46,614,080	21,418,000	1,019,000	2,310,144
17	Mar 19, 2026 08:15	8,982	46,459,287	19,394,000	3,062,000	2,293,760
18	Mar 19, 2026 08:04	8,998	45,476,757	16,360,000	6,135,000	2,265,088
19	Mar 19, 2026 08:02	8,999	45,517,589	17,385,000	5,113,000	2,322,432
20	Mar 19, 2026 08:18	9,006	45,163,093	19,446,000	3,070,000	2,301,952
21	Mar 19, 2026 08:26	9,012	52,319,580	17,411,000	5,120,000	2,334,720
22	Mar 19, 2026 08:09	9,015	41,964,427	18,440,000	4,097,000	2,449,408
23	Mar 19, 2026 08:15	9,017	45,861,359	19,468,000	3,074,000	2,310,144
24	Mar 19, 2026 08:18	9,018	45,446,323	19,472,000	3,074,000	2,289,664
25	Mar 19, 2026 08:04	9,020	48,150,275	18,451,000	4,100,000	2,273,280
26	Mar 19, 2026 08:18	9,033	45,139,143	20,530,000	2,053,000	2,289,664
27	Mar 19, 2026 08:15	9,045	49,554,678	20,557,000	2,055,000	2,506,752
28	Mar 19, 2026 08:18	9,052	44,670,247	17,486,000	5,143,000	2,281,472
29	Mar 19, 2026 08:18	9,074	47,227,498	17,529,000	5,155,000	2,326,528
30	Mar 19, 2026 08:13	9,085	46,150,433	15,800,000	6,912,000	2,506,752
31	Mar 19, 2026 08:02	9,094	51,713,734	19,636,000	3,100,000	2,293,760
32	Mar 19, 2026 08:20	9,102	52,654,545	17,583,000	5,171,000	2,289,664
33	Mar 19, 2026 08:13	9,140	53,241,054	16,889,000	5,960,000	2,514,944
34	Mar 19, 2026 08:13	9,140	50,443,919	17,884,000	4,967,000	2,330,624
35	Mar 19, 2026 08:09	9,156	51,301,908	18,910,000	3,981,000	2,379,776
36	Mar 19, 2026 08:26	9,191	45,716,824	19,980,000	2,997,000	2,289,664
37	Mar 19, 2026 08:20	9,208	44,258,052	19,016,000	4,003,000	2,289,664
38	Mar 19, 2026 08:42	9,235	49,418,714	19,072,000	4,015,000	2,289,664
39	Mar 19, 2026 08:26	9,242	48,846,347	19,088,000	4,018,000	2,310,144
40	Mar 19, 2026 08:42	9,293	50,096,968	17,172,000	6,060,000	2,519,040
41	Mar 19, 2026 08:09	9,298	37,597,303	19,203,000	4,042,000	2,506,752
42	Mar 19, 2026 08:02	9,309	44,158,454	19,226,000	4,047,000	2,519,040

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