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	1:20.1.2-0ubuntu1~24.04.3	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	3.0.13-0ubuntu3.11	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.

Date	Author	Language	Status	Score
May 1, 2026 14:26	Victor Mercklé	CPPg++14.2.0	Success	3,132+14.21 RP
May 1, 2026 14:19	Victor Mercklé	CPPg++14.2.0	Success	3,146+707.06 RP
May 1, 2026 14:03	Victor Mercklé	ZIG0.16.0	Success	4,046+105.22 RP
May 1, 2026 13:45	Victor Mercklé	GOgo1.26.2	Success	5,978
May 1, 2026 13:38	Victor Mercklé	GOgo1.26.2	Success	4,222+41.34 RP
May 1, 2026 13:30	Victor Mercklé	GOgo1.26.2	Success	4,297+1'779.11 RP
May 1, 2026 13:18	Victor Mercklé	CSHARP10.0.7	Success	23,998
May 1, 2026 13:11	Victor Mercklé	ZIG0.16.0	Success	4,134+1'043.36 RP
May 1, 2026 12:57	Victor Mercklé	ZIG0.16.0	Success	23,224
May 1, 2026 12:50	Victor Mercklé	CSHARP10.0.7	Success	4,797+47.15 RP
May 1, 2026 12:37	Victor Mercklé	CSHARP10.0.7	Error
May 1, 2026 12:27	Victor Mercklé	CSHARP10.0.7	Success	10,413+703.26 RP
May 1, 2026 10:27	Victor Mercklé	CPPg++14.2.0	Success	4,384+834.47 RP
May 1, 2026 06:52	Charles Cabergs	CPPg++13.3.0	Success	4,630+124.83 RP
May 1, 2026 04:14	Charles Cabergs	CPPg++13.3.0	Success	4,914+126.61 RP
May 1, 2026 04:12	olliecrow	RUSTrust-1.94.0	Success	3,736
May 1, 2026 04:06	olliecrow	RUSTrust-1.94.0	Success	3,905
May 1, 2026 03:44	olliecrow	CPPclang++18.1.3	Success	3,754
Apr 30, 2026 23:38	olliecrow	RUSTrust-1.94.0	Success	3,754
Apr 30, 2026 23:14	olliecrow	CPPclang++18.1.3	Success	3,764
Apr 30, 2026 19:16	Victor Mercklé	CPPg++14.2.0	Error	+441.42 RP
Apr 30, 2026 19:06	Victor Mercklé	CPPg++14.2.0	Error	+317.51 RP
Apr 30, 2026 18:55	Victor Mercklé	CPPg++14.2.0	Success	14,543+222.33 RP
Apr 30, 2026 17:07	Charles Cabergs	CPPg++13.3.0	Success	5,240+160.76 RP
Apr 30, 2026 13:04	Victor Mercklé	CPPg++14.2.0	Success	122,206
Apr 30, 2026 09:34	Charles Cabergs	CPPg++13.3.0	Success	5,722+16.64 RP
Apr 30, 2026 01:26	Charles Cabergs	CPPg++13.3.0	Success	5,777+14.56 RP
Apr 29, 2026 22:04	olliecrow	RUSTrust-1.95.0	Success	3,899
Apr 29, 2026 21:37	olliecrow	CPPg++10.5.0	Success	4,129
Apr 29, 2026 17:23	Charles Cabergs	CPPg++13.3.0	Success	5,860
Apr 29, 2026 11:30	olliecrow	RUSTrust-1.95.0	Success	3,712+5.07 RP
Apr 29, 2026 11:08	olliecrow	CPPg++10.5.0	Success	4,154
Apr 29, 2026 05:35	olliecrow	RUSTrust-1.95.0	Success	3,747
Apr 29, 2026 05:18	olliecrow	CPPg++10.5.0	Success	4,034
Apr 29, 2026 05:12	olliecrow	CPPg++10.5.0	Success	4,281
Apr 28, 2026 23:08	Charles Cabergs	CPPg++13.3.0	Success	5,826+132.91 RP
Apr 28, 2026 21:20	olliecrow	RUSTrust-1.95.0	Success	3,952
Apr 28, 2026 21:03	olliecrow	CPPg++10.5.0	Success	4,090
Apr 28, 2026 08:57	TudyM	CPPg++14.2.0	Success	19,688
Apr 28, 2026 08:52	TudyM	CPPg++14.2.0	Success	19,645+59.66 RP
Apr 28, 2026 08:49	TudyM	CPPg++14.2.0	Success	22,262
Apr 28, 2026 08:45	TudyM	CPPg++14.2.0	Success	22,253+44.88 RP
Apr 28, 2026 08:36	TudyM	CPPg++14.2.0	Success	24,722+69.20 RP
Apr 28, 2026 08:30	TudyM	CPPg++14.2.0	Success	29,824+70.93 RP
Apr 28, 2026 08:26	TudyM	CPPg++14.2.0	Success	37,826+151.76 RP
Apr 28, 2026 08:21	TudyM	CPPg++14.2.0	Success	88,800+31.78 RP
Apr 28, 2026 08:17	TudyM	CPPg++14.2.0	Success	123,715+42.22 RP
Apr 28, 2026 08:14	TudyM	CPPg++14.2.0	Success	258,976+7.45 RP
Apr 28, 2026 00:37	Victor Mercklé	CPPg++14.2.0	Success	21,492+379.24 RP
Apr 28, 2026 00:30	Victor Mercklé	CPPg++14.2.0	Success	116,208+86.05 RP
Apr 28, 2026 00:23	Victor Mercklé	CPPg++14.2.0	Error
Apr 27, 2026 18:20	Charles Cabergs	CPPg++13.3.0	Success	7,051
Apr 27, 2026 16:11	Charles Cabergs	CPPg++13.3.0	Success	6,315+173.89 RP
Apr 27, 2026 05:41	olliecrow	RUSTrust-1.95.0	Success	3,719+288.51 RP
Apr 27, 2026 05:18	olliecrow	CPPclang++18.1.3	Success	4,166+18.86 RP
Apr 27, 2026 03:17	Charles Cabergs	CPPg++13.3.0	Success	7,136
Apr 27, 2026 00:38	Charles Cabergs	CPPg++13.3.0	Success	7,094+43.89 RP
Apr 26, 2026 20:48	TudyM	CPPg++14.2.0	Success	463,660
Apr 26, 2026 20:26	TudyM	CPPg++14.2.0	Success	320,886
Apr 26, 2026 20:25	TudyM	CPPg++14.2.0	Success	320,888+5.19 RP
Apr 26, 2026 20:24	TudyM	CPPclang++20.1.2	Success	497,641
Apr 26, 2026 20:23	TudyM	CPPg++14.2.0	Success	385,053+9.35 RP
Apr 26, 2026 17:34	TudyM	CPPg++10.5.0	Success	601,531+10.29 RP
Apr 26, 2026 17:26	TudyM	CPPg++10.5.0	Success	1,578,201+6.34 RP
Apr 26, 2026 11:26	olliecrow	RUSTrust-1.95.0	Success	4,257
Apr 26, 2026 11:04	olliecrow	CPPclang++18.1.3	Success	4,590
Apr 26, 2026 05:27	olliecrow	RUSTrust-1.95.0	Success	4,199+87.42 RP
Apr 26, 2026 05:25	Charles Cabergs	CPPg++13.3.0	Success	7,350
Apr 26, 2026 05:01	olliecrow	CPPclang++18.1.3	Success	4,663
Apr 26, 2026 04:54	olliecrow	CPPg++10.5.0	Success	4,975
Apr 26, 2026 00:35	olliecrow	RUSTrust-1.95.0	Success	4,359+45.40 RP
Apr 25, 2026 18:05	olliecrow	RUSTrust-1.95.0	Success	4,854
Apr 25, 2026 06:20	olliecrow	RUSTrust-1.95.0	Success	4,484
Apr 24, 2026 23:44	Charles Cabergs	CPPg++13.3.0	Success	7,322+125.98 RP
Apr 24, 2026 14:09	olliecrow	RUSTrust-1.95.0	Success	4,455
Apr 24, 2026 08:40	Dominique Garmier	CPPclang++20.1.2	Success	8,593
Apr 24, 2026 02:52	olliecrow	CPPclang++18.1.3	Success	4,874
Apr 23, 2026 19:01	olliecrow	CPPclang++18.1.3	Success	4,852
Apr 23, 2026 18:52	olliecrow	CPPg++10.5.0	Success	30,210
Apr 23, 2026 05:07	Charles Cabergs	CPPg++13.3.0	Success	8,066+47.31 RP
Apr 23, 2026 04:22	olliecrow	RUSTrust-1.95.0	Success	4,470
Apr 23, 2026 03:56	olliecrow	CPPclang++18.1.3	Success	4,844
Apr 22, 2026 23:23	Charles Cabergs	CPPg++13.3.0	Success	8,386+47.51 RP
Apr 22, 2026 21:47	Charles Cabergs	CPPg++13.3.0	Success	8,734+170.77 RP
Apr 22, 2026 21:15	olliecrow	RUSTrust-1.95.0	Success	4,447+29.94 RP
Apr 22, 2026 20:41	Dominique Garmier	CPPclang++20.1.2	Success	8,567
Apr 22, 2026 20:39	Dominique Garmier	CPPclang++20.1.2	Success	8,552
Apr 22, 2026 15:58	olliecrow	RUSTrust-1.95.0	Success	4,507+48.63 RP
Apr 22, 2026 15:10	Dominique Garmier	CSHARP9.0.15	Success	82,773
Apr 22, 2026 14:57	Dominique Garmier	GOgo1.26.1	Success	33,921
Apr 22, 2026 14:00	Ben	CPPclang++18.1.3	Success	28,176
Apr 22, 2026 11:45	Dominique Garmier	CPPclang++20.1.2	Success	8,577
Apr 22, 2026 05:38	olliecrow	ZIG0.14.0	Success	6,607+303.62 RP
Apr 22, 2026 05:33	olliecrow	ZIG0.14.0	Error
Apr 22, 2026 04:39	olliecrow	CSHARP9.0.15	Success	44,421
Apr 22, 2026 04:15	olliecrow	CSHARP9.0.15	Error
Apr 21, 2026 19:21	Charles Cabergs	CPPg++13.3.0	Success	11,888
Apr 21, 2026 17:22	Charles Cabergs	CPPg++13.3.0	Success	10,265+38.38 RP
Apr 21, 2026 17:10	olliecrow	CPPclang++18.1.3	Success	4,972
Apr 21, 2026 15:24	Charles Cabergs	CPPg++13.3.0	Success	10,686+43.35 RP

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