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 20, 2026 08:08

Dominique GarmierScore: 8,774Success

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Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory
1	Mar 20, 2026 09:07	8,684	47,586,129	18,609,000	3,101,000	2,277,376
2	Mar 20, 2026 09:03	8,697	43,016,002	18,637,000	3,106,000	2,273,280
3	Mar 20, 2026 08:55	8,751	52,827,565	18,894,000	2,983,000	2,351,104
4	Mar 20, 2026 08:33	8,754	47,579,381	18,901,000	2,984,000	2,334,720
5	Mar 20, 2026 08:55	8,755	49,153,588	15,919,000	5,969,000	2,314,240
6	Mar 20, 2026 09:42	8,756	50,613,690	17,910,000	3,980,000	2,351,104
7	Mar 20, 2026 08:21	8,756	50,400,305	17,910,000	3,980,000	2,277,376
8	Mar 20, 2026 08:33	8,756	51,304,140	16,915,000	4,975,000	2,265,088
9	Mar 20, 2026 09:18	8,757	45,355,190	17,913,000	3,980,000	2,465,792
10	Mar 20, 2026 08:33	8,758	47,504,763	19,906,000	1,990,000	2,265,088
11	Mar 20, 2026 08:49	8,758	45,200,826	18,910,000	2,985,000	2,269,184
12	Mar 20, 2026 09:14	8,759	48,558,331	18,911,000	2,986,000	2,277,376
13	Mar 20, 2026 09:18	8,760	50,992,726	15,927,000	5,972,000	2,277,376
14	Mar 20, 2026 08:55	8,762	54,047,009	19,915,000	1,991,000	2,277,376
15	Mar 20, 2026 08:08	8,763	48,103,843	20,864,000	1,043,000	2,519,040
16	Mar 20, 2026 08:49	8,763	50,204,742	17,924,000	3,983,000	2,338,816
17	Mar 20, 2026 09:03	8,764	47,458,895	19,919,000	1,991,000	2,367,488
18	Mar 20, 2026 08:01	8,764	47,261,553	19,918,000	1,991,000	2,277,376
19	Mar 20, 2026 09:07	8,765	47,153,088	15,936,000	5,976,000	2,277,376
20	Mar 20, 2026 10:17	8,766	47,940,915	16,935,000	4,980,000	2,269,184
21	Mar 20, 2026 09:42	8,769	44,165,668	18,934,000	2,989,000	2,363,392
22	Mar 20, 2026 08:49	8,774	47,621,073	18,944,000	2,991,000	2,396,160
23	Mar 20, 2026 08:01	8,777	47,551,571	20,945,000	997,000	2,502,656
24	Mar 20, 2026 09:14	8,804	46,041,287	17,008,000	5,002,000	2,273,280
25	Mar 20, 2026 09:18	8,816	49,621,571	18,032,000	4,007,000	2,289,664
26	Mar 20, 2026 08:21	8,827	47,028,661	18,056,000	4,012,000	2,297,856
27	Mar 20, 2026 09:42	8,827	48,233,595	19,059,000	3,009,000	2,277,376
28	Mar 20, 2026 09:07	8,830	48,159,617	18,062,000	4,013,000	2,277,376
29	Mar 20, 2026 08:34	8,837	46,531,753	17,071,000	5,021,000	2,289,664
30	Mar 20, 2026 09:03	8,894	46,575,490	16,172,000	6,064,000	2,277,376
31	Mar 20, 2026 10:27	8,922	44,186,486	19,264,000	3,041,000	2,277,376
32	Mar 20, 2026 10:27	8,964	46,245,232	18,335,000	4,074,000	2,277,376
33	Mar 20, 2026 08:34	8,972	49,983,406	19,373,000	3,058,000	2,482,176
34	Mar 20, 2026 08:34	8,979	49,661,399	18,366,000	4,081,000	2,437,120
35	Mar 20, 2026 10:17	9,004	48,934,792	19,442,000	3,069,000	2,506,752
36	Mar 20, 2026 08:08	9,005	46,458,169	18,420,000	4,093,000	2,269,184
37	Mar 20, 2026 08:01	9,008	43,793,773	18,426,000	4,094,000	2,322,432
38	Mar 20, 2026 10:17	9,009	49,459,250	19,452,000	3,071,000	2,334,720
39	Mar 20, 2026 08:21	9,024	49,243,480	15,382,000	7,178,000	2,260,992
40	Mar 20, 2026 08:08	9,035	42,756,215	16,427,000	6,160,000	2,498,560
41	Mar 20, 2026 10:27	9,069	48,762,606	18,551,000	4,122,000	2,314,240
42	Mar 20, 2026 09:14	9,091	49,051,155	19,629,000	3,099,000	2,273,280

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