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 27, 2026 18:26	Elijah Kin	CPPg++14.2.0	Success	6,213+108.48 RP
May 27, 2026 18:23	Elijah Kin	CPPg++14.2.0	Success	6,662+17.81 RP
May 27, 2026 17:01	Elijah Kin	CPPclang++20.1.2	Success	11,103
May 27, 2026 16:59	Elijah Kin	CPPg++14.2.0	Success	6,742+35.64 RP
May 27, 2026 16:46	Elijah Kin	CPPg++14.2.0	Success	6,908+376.70 RP
May 26, 2026 17:19	Elijah Kin	CPPg++14.2.0	Success	9,854
May 26, 2026 17:04	Elijah Kin	CPPg++14.2.0	Success	9,338+93.57 RP
May 26, 2026 17:02	Elijah Kin	CPPclang++20.1.2	Success	11,061
May 26, 2026 16:48	Elijah Kin	CPPclang++20.1.2	Success	11,166
May 25, 2026 22:14	Elijah Kin	CPPclang++20.1.2	Success	13,925
May 22, 2026 13:11	M-Rochat	CPPclang++17.0.6	Success	4,307
May 22, 2026 13:09	M-Rochat	CPPclang++17.0.6	Success	4,307
May 22, 2026 13:08	M-Rochat	CPPclang++17.0.6	Success	4,317
May 22, 2026 13:07	M-Rochat	CPPclang++17.0.6	Success	4,302+4.31 RP
May 22, 2026 13:04	M-Rochat	CPPclang++17.0.6	Success	4,310+32.90 RP
May 22, 2026 13:03	M-Rochat	CPPclang++17.0.6	Success	4,481
May 22, 2026 13:02	M-Rochat	CPPclang++17.0.6	Success	4,498
May 22, 2026 13:00	M-Rochat	CPPclang++20.1.2	Success	4,496
May 22, 2026 12:58	M-Rochat	CPPclang++17.0.6	Success	4,472
May 22, 2026 12:57	M-Rochat	CPPclang++17.0.6	Success	4,441
May 22, 2026 12:55	M-Rochat	CPPclang++17.0.6	Success	4,487
May 22, 2026 12:54	M-Rochat	CPPclang++17.0.6	Success	4,495
May 22, 2026 12:52	M-Rochat	CPPclang++17.0.6	Success	4,372+1.57 RP
May 22, 2026 12:50	M-Rochat	CPPclang++17.0.6	Success	4,688
May 22, 2026 09:56	M-Rochat	CPPclang++17.0.6	Success	4,699
May 22, 2026 09:54	M-Rochat	CPPg++13.3.0	Success	4,673
May 22, 2026 09:53	M-Rochat	CPPclang++17.0.6	Success	4,568
May 22, 2026 09:51	M-Rochat	CPPclang++17.0.6	Success	4,692
May 22, 2026 09:50	M-Rochat	CPPclang++17.0.6	Success	4,689
May 22, 2026 09:48	M-Rochat	CPPclang++20.1.2	Success	4,682
May 22, 2026 09:47	M-Rochat	CPPclang++17.0.6	Success	4,762
May 22, 2026 09:45	M-Rochat	CPPclang++17.0.6	Success	4,674
May 22, 2026 09:43	M-Rochat	CPPclang++17.0.6	Success	4,737
May 22, 2026 09:41	M-Rochat	CPPclang++17.0.6	Success	4,684
May 21, 2026 22:23	Jacob McDaniel	CPPg++14.2.0	Success	2,922
May 21, 2026 22:07	Jacob McDaniel	CPPclang++20.1.2	Success	2,726
May 21, 2026 22:06	Jacob McDaniel	CPPg++12.4.0	Success	2,509
May 21, 2026 22:06	Jacob McDaniel	CPPg++13.3.0	Success	2,476
May 21, 2026 21:57	Jacob McDaniel	CPPg++14.2.0	Success	2,548
May 21, 2026 21:56	Jacob McDaniel	CPPg++14.2.0	Success	2,467
May 21, 2026 21:56	Jacob McDaniel	CPPg++14.2.0	Success	2,516
May 21, 2026 18:58	Jacob McDaniel	CPPg++14.2.0	Success	2,516
May 21, 2026 18:57	Jacob McDaniel	CPPg++14.2.0	Success	2,602
May 21, 2026 18:57	Jacob McDaniel	CPPg++14.2.0	Success	2,563
May 21, 2026 18:52	Jacob McDaniel	CPPg++14.2.0	Success	2,576
May 21, 2026 18:52	Jacob McDaniel	CPPg++14.2.0	Success	2,543
May 21, 2026 18:46	Jacob McDaniel	CPPg++14.2.0	Success	2,572
May 21, 2026 18:45	Jacob McDaniel	CPPg++14.2.0	Success	2,526
May 21, 2026 18:44	Jacob McDaniel	CPPg++14.2.0	Success	2,505
May 21, 2026 18:44	Jacob McDaniel	CPPg++14.2.0	Success	2,458+36.26 RP
May 21, 2026 18:33	Jacob McDaniel	CPPg++14.2.0	Success	2,606
May 21, 2026 18:32	Jacob McDaniel	CPPg++14.2.0	Success	2,492
May 21, 2026 18:31	Jacob McDaniel	CPPg++14.2.0	Success	2,469+97.24 RP
May 21, 2026 18:31	Jacob McDaniel	CPPg++14.2.0	Success	2,539
May 21, 2026 05:10	Jacob McDaniel	CPPclang++20.1.2	Success	2,738
May 21, 2026 05:08	Jacob McDaniel	CPPg++14.2.0	Success	2,654
May 21, 2026 05:08	Jacob McDaniel	CPPg++14.2.0	Success	2,499+54.08 RP
May 20, 2026 17:40	Jacob McDaniel	CPPg++14.2.0	Success	2,532
May 20, 2026 16:53	M-Rochat	CPPclang++17.0.6	Success	4,686
May 20, 2026 16:52	M-Rochat	CPPclang++17.0.6	Success	4,558
May 20, 2026 16:51	M-Rochat	CPPclang++17.0.6	Success	4,675
May 20, 2026 16:50	M-Rochat	CPPclang++17.0.6	Success	4,690
May 20, 2026 16:50	M-Rochat	CPPclang++17.0.6	Success	4,552
May 20, 2026 16:49	M-Rochat	CPPclang++18.1.3	Success	4,558
May 20, 2026 16:47	M-Rochat	CPPclang++17.0.6	Success	4,761
May 20, 2026 16:46	M-Rochat	CPPclang++17.0.6	Success	6,672
May 20, 2026 16:44	M-Rochat	CPPclang++17.0.6	Success	4,622
May 20, 2026 16:43	M-Rochat	CPPclang++17.0.6	Success	4,718
May 20, 2026 16:41	M-Rochat	CPPclang++17.0.6	Success	4,670
May 20, 2026 16:39	M-Rochat	CPPclang++17.0.6	Success	4,681
May 20, 2026 16:37	M-Rochat	CPPclang++17.0.6	Success	4,562
May 20, 2026 16:36	M-Rochat	CPPclang++17.0.6	Success	4,564
May 20, 2026 16:36	M-Rochat	CPPclang++17.0.6	Success	4,565
May 20, 2026 16:34	Victor Mercklé	CPPg++14.2.0	Success	2,815
May 20, 2026 16:34	M-Rochat	CPPclang++17.0.6	Success	4,610
May 20, 2026 16:31	M-Rochat	CPPclang++17.0.6	Success	4,554
May 20, 2026 16:30	M-Rochat	CPPclang++20.1.2	Success	4,558
May 20, 2026 16:29	M-Rochat	CPPclang++17.0.6	Success	4,568
May 20, 2026 16:28	M-Rochat	CPPclang++17.0.6	Success	4,555
May 20, 2026 16:27	M-Rochat	CPPclang++17.0.6	Success	4,708
May 20, 2026 16:27	M-Rochat	CPPclang++17.0.6	Success	4,666
May 20, 2026 16:26	M-Rochat	CPPclang++17.0.6	Success	4,554
May 20, 2026 16:25	M-Rochat	CPPclang++17.0.6	Success	4,584
May 20, 2026 16:24	Victor Mercklé	CPPg++14.2.0	Success	2,833
May 20, 2026 16:24	M-Rochat	CPPclang++17.0.6	Success	4,688
May 20, 2026 16:22	M-Rochat	CPPclang++17.0.6	Error
May 20, 2026 16:19	Victor Mercklé	CPPg++14.2.0	Success	2,790
May 20, 2026 16:19	M-Rochat	CPPclang++17.0.6	Success	4,688
May 20, 2026 16:18	M-Rochat	CPPclang++17.0.6	Success	4,562
May 20, 2026 16:13	Victor Mercklé	CPPg++14.2.0	Success	2,722
May 20, 2026 15:46	Victor Mercklé	CPPg++14.2.0	Success	2,743
May 20, 2026 15:41	Victor Mercklé	CPPg++14.2.0	Success	2,762
May 20, 2026 15:36	Victor Mercklé	CPPg++14.2.0	Success	2,786
May 20, 2026 15:31	Victor Mercklé	CPPg++14.2.0	Success	2,827
May 20, 2026 15:23	Victor Mercklé	CPPg++14.2.0	Success	2,730
May 20, 2026 15:17	Victor Mercklé	CPPg++14.2.0	Success	2,782
May 20, 2026 15:12	Victor Mercklé	CPPg++14.2.0	Success	2,835
May 20, 2026 15:02	Victor Mercklé	CPPg++14.2.0	Success	2,760
May 20, 2026 14:59	Victor Mercklé	CPPg++14.2.0	Success	2,780
May 20, 2026 14:56	Victor Mercklé	CPPg++14.2.0	Success	2,806

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