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 16, 2026 23:09	M-Rochat	CPPg++14.2.0	Error
May 16, 2026 23:09	M-Rochat	CPPg++14.2.0	Error
May 16, 2026 23:09	M-Rochat	CPPg++14.2.0	Error
May 16, 2026 23:05	Jacob McDaniel	CPPg++14.2.0	Success	11,248+42.81 RP
May 16, 2026 22:55	Jacob McDaniel	CPPg++14.2.0	Success	11,817+15.54 RP
May 16, 2026 22:53	Jacob McDaniel	CPPg++10.5.0	Success	12,038+3.71 RP
May 16, 2026 22:18	Jacob McDaniel	CPPg++14.2.0	Success	12,092+173.95 RP
May 16, 2026 21:57	Jacob McDaniel	CPPg++14.2.0	Success	15,313+243.19 RP
May 16, 2026 21:21	Jacob McDaniel	CPPg++14.2.0	Success	24,399+35.41 RP
May 16, 2026 21:04	Jacob McDaniel	CPPg++14.2.0	Success	26,706+365.28 RP
May 16, 2026 20:43	Jacob McDaniel	CPPg++14.2.0	Success	1,090,621+2.81 RP
May 16, 2026 19:28	M-Rochat	CPPg++14.2.0	Error
May 16, 2026 19:26	M-Rochat	CPPg++14.2.0	Error
May 16, 2026 11:01	Jacob McDaniel	CPPg++10.5.0	Success	1,573,350+6.36 RP
May 16, 2026 07:24	M-Rochat	CPPg++14.2.0	Success	24,588+1.65 RP
May 15, 2026 19:32	M-Rochat	CPPg++14.2.0	Success	24,688+405.06 RP
May 14, 2026 17:13	Josu San Martin	CSHARP9.0.13	Success	1,249,068
May 14, 2026 17:11	Josu San Martin	ZIG0.15.1	Success	1,055,841+5.00 RP
May 13, 2026 09:06	Victor Mercklé	CPPg++14.2.0	Success	114,669
May 11, 2026 21:06	Victor Mercklé	GOgo1.26.2	Success	3,889+13.81 RP
May 11, 2026 20:52	Victor Mercklé	CSHARP10.0.7	Success	4,221+284.47 RP
May 11, 2026 20:43	Victor Mercklé	GOgo1.26.2	Success	3,910+189.00 RP
May 11, 2026 20:27	Victor Mercklé	RUSTrust-1.95.0	Success	2,933+129.71 RP
May 11, 2026 19:37	Victor Mercklé	CPPg++14.2.0	Success	2,825+410.05 RP
May 11, 2026 18:33	Victor Mercklé	RUSTrust-1.95.0	Success	3,049+532.29 RP
May 10, 2026 23:47	Elijah Kin	CPPclang++20.1.2	Success	12,921
May 7, 2026 06:52	Victor Mercklé	CPPg++14.2.0	Error
May 5, 2026 19:19	olliecrow	GOgo1.26.2	Success	34,175
May 5, 2026 19:14	olliecrow	GOgo1.26.2	Success	34,757
May 5, 2026 19:04	olliecrow	GOgo1.26.2	Success	26,793
May 5, 2026 15:46	olliecrow	GOgo1.26.2	Error
May 5, 2026 15:19	olliecrow	GOgo1.26.2	Error
May 5, 2026 14:47	olliecrow	GOgo1.26.2	Error
May 5, 2026 14:33	olliecrow	CSHARP9.0.15	Success	8,534
May 5, 2026 14:28	olliecrow	CSHARP9.0.15	Success	8,566
May 5, 2026 14:13	Victor Mercklé	ZIG0.16.0	Success	3,242+612.94 RP
May 5, 2026 03:51	olliecrow	RUSTrust-1.95.0	Success	4,030
May 5, 2026 03:41	olliecrow	RUSTrust-1.95.0	Success	3,882
May 5, 2026 01:28	olliecrow	CPPclang++18.1.3	Success	3,914
May 5, 2026 01:22	olliecrow	RUSTrust-1.95.0	Success	3,975
May 5, 2026 01:15	olliecrow	CPPclang++18.1.3	Success	3,954
May 5, 2026 01:15	olliecrow	RUSTrust-1.95.0	Success	3,834
May 5, 2026 00:50	olliecrow	CPPclang++18.1.3	Success	4,084
May 5, 2026 00:41	olliecrow	CPPclang++18.1.3	Success	3,755
May 5, 2026 00:13	olliecrow	CPPclang++18.1.3	Success	4,157
May 5, 2026 00:09	olliecrow	CPPclang++18.1.3	Success	4,165
May 4, 2026 23:53	olliecrow	CPPclang++18.1.3	Success	4,068
May 4, 2026 23:03	olliecrow	CPPclang++18.1.3	Success	3,830
May 4, 2026 22:58	olliecrow	CPPclang++18.1.3	Success	3,785
May 4, 2026 22:48	olliecrow	CPPclang++18.1.3	Success	3,961
May 4, 2026 22:39	olliecrow	CPPclang++18.1.3	Success	3,917
May 4, 2026 21:54	olliecrow	CPPclang++18.1.3	Success	3,876
May 4, 2026 11:25	Victor Mercklé	CSHARP10.0.7	Success	83,067
May 4, 2026 11:01	Victor Mercklé	CPPg++14.2.0	Success	118,052
May 4, 2026 10:44	Victor Mercklé	CPPg++14.2.0	Success	118,848
May 4, 2026 10:31	Victor Mercklé	CPPg++14.2.0	Success	114,860
May 4, 2026 09:13	Victor Mercklé	CPPg++14.2.0	Success	119,050
May 4, 2026 08:25	Victor Mercklé	CPPg++14.2.0	Success	3,105+27.76 RP
May 2, 2026 06:48	Victor Mercklé	CSHARP10.0.7	Success	82,226
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	Success	4,908+1'077.15 RP
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	Success	6,913+441.42 RP
Apr 30, 2026 19:06	Victor Mercklé	CPPg++14.2.0	Success	9,949+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

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