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
Sep 14, 2026 00:59	Andrew Epstein	ZIG0.15.1	Success	1,369+84.39 RP
Sep 14, 2026 00:54	Andrew Epstein	ZIG0.15.1	Success	1,407
Sep 14, 2026 00:51	Andrew Epstein	ZIG0.15.1	Success	1,416
Sep 14, 2026 00:49	Andrew Epstein	GOgo1.26.2	Success	1,518+1'050.52 RP
Sep 14, 2026 00:42	Andrew Epstein	ZIG0.15.1	Success	1,504
Sep 14, 2026 00:32	Andrew Epstein	CPPg++14.2.0	Success	1,384+5.22 RP
Sep 14, 2026 00:29	Andrew Epstein	RUSTrust-1.95.0	Success	1,342+593.43 RP
Sep 14, 2026 00:28	Andrew Epstein	CPPg++14.2.0	Success	1,420+290.06 RP
Sep 14, 2026 00:24	Andrew Epstein	CPPg++14.2.0	Success	1,481+58.75 RP
Sep 14, 2026 00:23	Andrew Epstein	CPPg++14.2.0	Success	1,494+324.01 RP
Sep 14, 2026 00:19	Andrew Epstein	CPPg++14.2.0	Success	1,634
Sep 13, 2026 23:29	Andrew Epstein	CSHARP10.0.8	Success	1,613+1'347.61 RP
Sep 10, 2026 17:22	Victor Mercklé	CPPg++14.2.0	Success	1,576
Sep 10, 2026 16:37	Andrew Epstein	CSHARP9.0.15	Success	2,083
Sep 10, 2026 16:36	Victor Mercklé	CPPg++14.2.0	Success	1,544
Sep 10, 2026 16:35	Andrew Epstein	CSHARP10.0.8	Success	2,061+135.03 RP
Sep 10, 2026 16:22	Andrew Epstein	CSHARP10.0.8	Success	2,134
Sep 10, 2026 16:21	Victor Mercklé	CPPg++14.2.0	Success	1,523
Sep 10, 2026 16:11	Andrew Epstein	CPPg++14.2.0	Success	1,570+319.82 RP
Sep 10, 2026 16:03	Victor Mercklé	CPPg++14.2.0	Success	1,544
Sep 10, 2026 12:17	Victor Mercklé	ZIG0.16.0	Success	2,562
Sep 10, 2026 10:52	Victor Mercklé	ZIG0.16.0	Success	2,613
Sep 10, 2026 09:52	Victor Mercklé	RUSTrust-1.95.0	Success	2,655
Sep 10, 2026 09:30	Victor Mercklé	RUSTrust-1.95.0	Success	2,593
Sep 10, 2026 09:28	Victor Mercklé	GOgo1.26.2	Success	2,465
Sep 10, 2026 09:17	Victor Mercklé	GOgo1.26.2	Success	2,472
Sep 10, 2026 09:12	Victor Mercklé	CSHARP10.0.7	Success	3,568
Sep 10, 2026 08:58	Victor Mercklé	CSHARP10.0.7	Success	3,500
Sep 10, 2026 08:45	Victor Mercklé	CPPg++14.2.0	Success	1,457+4.71 RP
Sep 10, 2026 08:40	Victor Mercklé	CPPg++14.2.0	Success	1,469
Sep 10, 2026 08:34	Victor Mercklé	CPPg++14.2.0	Success	1,564
Sep 10, 2026 08:32	Victor Mercklé	ZIG0.16.0	Success	3,065
Sep 10, 2026 08:22	Victor Mercklé	ZIG0.16.0	Success	3,020
Sep 10, 2026 08:15	Victor Mercklé	RUSTrust-1.95.0	Success	2,718
Sep 10, 2026 08:05	Victor Mercklé	RUSTrust-1.95.0	Success	3,026
Sep 10, 2026 07:57	Victor Mercklé	GOgo1.26.2	Success	2,504
Sep 10, 2026 07:46	Victor Mercklé	GOgo1.26.2	Success	2,481
Sep 10, 2026 03:00	Andrew Epstein	CPPclang++20.1.2	Success	1,760
Sep 9, 2026 17:48	Victor Mercklé	CSHARP10.0.7	Success	4,304
Sep 9, 2026 17:03	Victor Mercklé	CSHARP10.0.7	Success	3,495
Sep 9, 2026 16:50	Victor Mercklé	CSHARP10.0.7	Success	4,298
Sep 9, 2026 16:06	Victor Mercklé	CPPg++14.2.0	Success	1,547
Sep 9, 2026 15:57	Victor Mercklé	CPPg++14.2.0	Success	1,678
Sep 9, 2026 14:22	Victor Mercklé	CPPg++14.2.0	Success	1,546
Sep 5, 2026 01:46	Victor Mercklé	CPPg++14.2.0	Success	1,551
Sep 5, 2026 01:25	Victor Mercklé	CPPg++14.2.0	Success	1,575
Sep 5, 2026 00:54	Victor Mercklé	CPPg++14.2.0	Success	1,550
Sep 5, 2026 00:28	Victor Mercklé	CPPg++14.2.0	Success	1,550
Sep 4, 2026 23:49	Victor Mercklé	CPPg++14.2.0	Success	3,032
Sep 4, 2026 16:06	Victor Mercklé	CPPg++14.2.0	Success	1,510
Sep 4, 2026 08:53	Victor Mercklé	CPPg++14.2.0	Success	1,476
Sep 4, 2026 08:06	Victor Mercklé	CPPg++14.2.0	Success	1,480
Sep 4, 2026 07:44	Victor Mercklé	CPPg++14.2.0	Success	1,498
Sep 4, 2026 07:18	Victor Mercklé	CPPg++14.2.0	Success	1,476
Aug 31, 2026 13:20	Victor Mercklé	CPPg++14.2.0	Error
Aug 31, 2026 02:12	Tomislav Tunkovic	GOgo1.26.2	Success	1,961
Aug 31, 2026 02:05	Tomislav Tunkovic	CPPg++14.2.0	Success	1,486
Aug 31, 2026 02:04	Tomislav Tunkovic	CPPg++14.2.0	Success	1,537
Aug 31, 2026 01:58	Tomislav Tunkovic	CPPg++14.2.0	Success	1,534
Aug 31, 2026 01:58	Tomislav Tunkovic	CSHARP9.0.15	Success	2,166
Aug 31, 2026 01:57	Tomislav Tunkovic	CSHARP9.0.15	Success	2,120
Aug 31, 2026 01:55	Tomislav Tunkovic	CPPg++14.2.0	Success	1,526
Aug 31, 2026 01:55	Tomislav Tunkovic	GOgo1.26.2	Success	1,848
Aug 31, 2026 01:54	Tomislav Tunkovic	CPPg++14.2.0	Success	1,385+20.79 RP
Aug 31, 2026 01:53	Tomislav Tunkovic	CPPg++14.2.0	Error
Aug 31, 2026 01:52	Tomislav Tunkovic	ZIG0.15.1	Success	1,385+389.62 RP
Aug 31, 2026 01:52	Tomislav Tunkovic	CPPg++14.2.0	Success	1,389+87.05 RP
Aug 31, 2026 01:47	Tomislav Tunkovic	CPPg++14.2.0	Success	1,501
Aug 31, 2026 01:45	Tomislav Tunkovic	RUSTrust-1.95.0	Success	1,376+42.14 RP
Aug 31, 2026 01:40	Tomislav Tunkovic	RUSTrust-1.95.0	Success	1,380+650.90 RP
Aug 31, 2026 01:34	Tomislav Tunkovic	RUSTrust-1.95.0	Success	1,526
Aug 31, 2026 01:26	Victor Mercklé	CPPg++14.2.0	Success	1,577
Aug 31, 2026 01:23	Tomislav Tunkovic	RUSTrust-1.95.0	Success	1,535
Aug 31, 2026 01:12	Tomislav Tunkovic	CPPg++14.2.0	Success	1,532
Aug 31, 2026 01:11	Victor Mercklé	CPPg++14.2.0	Success	1,496
Aug 31, 2026 01:06	Tomislav Tunkovic	CPPg++14.2.0	Success	1,536
Aug 31, 2026 00:59	Tomislav Tunkovic	CPPg++14.2.0	Success	1,492
Aug 31, 2026 00:56	Victor Mercklé	CPPg++14.2.0	Success	1,597
Aug 31, 2026 00:54	Tomislav Tunkovic	RUSTrust-1.95.0	Success	1,552
Aug 31, 2026 00:53	Tomislav Tunkovic	CPPg++14.2.0	Success	1,531
Aug 31, 2026 00:47	Tomislav Tunkovic	CPPg++14.2.0	Success	1,515
Aug 31, 2026 00:43	Victor Mercklé	CPPg++14.2.0	Success	1,554
Aug 31, 2026 00:42	Tomislav Tunkovic	CPPg++14.2.0	Success	1,517
Aug 31, 2026 00:39	Tomislav Tunkovic	CPPg++14.2.0	Success	1,438
Aug 31, 2026 00:35	Tomislav Tunkovic	CPPg++14.2.0	Success	1,534
Aug 31, 2026 00:28	Tomislav Tunkovic	ZIG0.15.1	Success	1,537
Aug 31, 2026 00:23	Tomislav Tunkovic	CPPg++14.2.0	Success	1,537
Aug 31, 2026 00:19	Tomislav Tunkovic	CPPg++14.2.0	Success	1,532
Aug 31, 2026 00:15	Tomislav Tunkovic	CPPg++14.2.0	Success	1,508
Aug 31, 2026 00:08	Tomislav Tunkovic	CPPg++14.2.0	Success	1,540
Aug 31, 2026 00:05	Tomislav Tunkovic	CPPg++14.2.0	Success	1,520
Aug 31, 2026 00:01	Victor Mercklé	CPPg++14.2.0	Success	1,458+51.36 RP
Aug 30, 2026 23:52	Tomislav Tunkovic	CPPg++14.2.0	Success	1,517
Aug 30, 2026 23:51	Tomislav Tunkovic	ZIG0.15.1	Success	1,464+64.70 RP
Aug 30, 2026 23:44	Tomislav Tunkovic	RUSTrust-1.95.0	Success	1,528
Aug 30, 2026 23:39	Tomislav Tunkovic	CSHARP9.0.15	Success	2,182
Aug 30, 2026 23:36	Tomislav Tunkovic	GOgo1.26.2	Success	1,806+522.05 RP
Aug 30, 2026 23:30	Tomislav Tunkovic	ZIG0.15.1	Success	1,518
Aug 30, 2026 23:28	Tomislav Tunkovic	RUSTrust-1.95.0	Success	1,545
Aug 30, 2026 23:20	Tomislav Tunkovic	CPPg++14.2.0	Success	1,406+911.21 RP

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