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 20, 2026 14:53	Victor Mercklé	CPPg++14.2.0	Success	2,795
May 20, 2026 14:49	Victor Mercklé	CPPg++14.2.0	Success	2,772
May 20, 2026 14:47	Victor Mercklé	CPPg++14.2.0	Success	2,790
May 20, 2026 14:44	Victor Mercklé	CPPg++14.2.0	Success	2,730
May 20, 2026 14:39	Victor Mercklé	CPPg++14.2.0	Success	2,756
May 20, 2026 14:36	Victor Mercklé	CPPg++14.2.0	Success	2,731
May 20, 2026 14:34	Victor Mercklé	CPPg++14.2.0	Success	2,757
May 20, 2026 14:31	Victor Mercklé	CPPg++14.2.0	Success	2,758
May 20, 2026 14:28	Victor Mercklé	CPPg++14.2.0	Success	2,719+10.79 RP
May 20, 2026 14:26	Victor Mercklé	CPPg++14.2.0	Success	2,727+30.67 RP
May 20, 2026 14:23	Victor Mercklé	CPPg++14.2.0	Success	2,750+22.34 RP
May 20, 2026 14:21	Victor Mercklé	CPPg++14.2.0	Success	2,844
May 20, 2026 14:18	Victor Mercklé	CPPg++14.2.0	Success	2,828
May 20, 2026 14:16	Victor Mercklé	CPPg++14.2.0	Success	2,782
May 20, 2026 14:14	Victor Mercklé	CPPg++14.2.0	Success	2,845
May 20, 2026 14:11	Victor Mercklé	CPPg++14.2.0	Success	2,870
May 20, 2026 14:08	Victor Mercklé	CPPg++14.2.0	Success	2,920
May 20, 2026 14:06	Victor Mercklé	CPPg++14.2.0	Success	2,864
May 20, 2026 14:03	Victor Mercklé	CPPg++14.2.0	Success	2,831
May 20, 2026 14:00	Victor Mercklé	CPPg++14.2.0	Success	2,805
May 20, 2026 13:58	Victor Mercklé	CPPg++14.2.0	Success	2,854
May 20, 2026 13:46	Victor Mercklé	CPPg++14.2.0	Success	2,861
May 20, 2026 13:44	Victor Mercklé	CPPg++14.2.0	Success	2,767+1.31 RP
May 20, 2026 13:42	Victor Mercklé	CPPg++14.2.0	Success	2,788
May 20, 2026 13:39	Victor Mercklé	CPPg++14.2.0	Success	2,934
May 20, 2026 13:36	Victor Mercklé	CPPg++14.2.0	Success	2,777
May 20, 2026 13:31	Jacob McDaniel	CPPg++14.2.0	Success	2,650
May 20, 2026 13:27	Victor Mercklé	CPPg++14.2.0	Success	2,801
May 20, 2026 13:19	Jacob McDaniel	CPPg++14.2.0	Success	2,584
May 20, 2026 13:17	Victor Mercklé	CPPg++14.2.0	Success	2,822
May 20, 2026 13:12	Victor Mercklé	CPPg++14.2.0	Success	2,832
May 20, 2026 13:07	Victor Mercklé	CPPg++14.2.0	Success	2,867
May 20, 2026 13:05	Victor Mercklé	CPPg++14.2.0	Success	2,840
May 20, 2026 13:03	Victor Mercklé	CPPg++14.2.0	Success	2,851
May 20, 2026 13:00	Victor Mercklé	CPPg++14.2.0	Success	2,768+20.76 RP
May 20, 2026 12:55	Victor Mercklé	CPPg++14.2.0	Success	2,784+39.56 RP
May 20, 2026 12:50	Victor Mercklé	CPPg++14.2.0	Success	2,815+7.56 RP
May 20, 2026 12:45	Victor Mercklé	CPPg++14.2.0	Success	2,821+5.02 RP
May 20, 2026 12:36	Victor Mercklé	CPPg++14.2.0	Success	2,892
May 20, 2026 12:30	Victor Mercklé	CPPg++14.2.0	Success	2,922
May 20, 2026 12:15	Jacob McDaniel	CPPg++14.2.0	Success	6,074
May 20, 2026 12:13	Jacob McDaniel	CPPg++14.2.0	Success	2,516+514.18 RP
May 20, 2026 12:11	Jacob McDaniel	CPPg++10.5.0	Success	2,757
May 20, 2026 12:11	Jacob McDaniel	CPPg++13.3.0	Success	2,796
May 20, 2026 11:21	Jacob McDaniel	CPPg++14.2.0	Success	2,768
May 20, 2026 11:17	Jacob McDaniel	CPPclang++20.1.2	Success	2,778
May 20, 2026 11:16	Jacob McDaniel	CPPg++14.2.0	Success	2,690+103.56 RP
May 20, 2026 11:02	Jacob McDaniel	CPPclang++20.1.2	Success	2,834
May 20, 2026 11:01	Jacob McDaniel	CPPg++14.2.0	Success	2,757
May 20, 2026 10:53	Jacob McDaniel	CPPg++14.2.0	Success	2,791
May 20, 2026 10:47	Jacob McDaniel	CPPg++11.5.0	Success	2,931
May 20, 2026 10:46	Jacob McDaniel	CPPg++14.2.0	Success	2,862
May 20, 2026 08:13	Jacob McDaniel	CPPclang++20.1.2	Success	2,763
May 20, 2026 08:12	Jacob McDaniel	CPPclang++14.0.6	Success	2,873
May 20, 2026 08:12	Jacob McDaniel	CPPclang++18.1.3	Success	2,753
May 20, 2026 08:12	Jacob McDaniel	CPPg++13.3.0	Success	2,800
May 20, 2026 08:07	Jacob McDaniel	CPPg++14.2.0	Success	2,789
May 20, 2026 08:07	Jacob McDaniel	CPPg++14.2.0	Success	2,944
May 20, 2026 08:06	Jacob McDaniel	CPPg++14.2.0	Success	2,806
May 19, 2026 21:20	Jacob McDaniel	CPPg++14.2.0	Success	2,794
May 19, 2026 21:09	Jacob McDaniel	CPPg++14.2.0	Success	2,728+32.10 RP
May 19, 2026 21:09	Jacob McDaniel	CPPg++14.2.0	Success	2,804
May 19, 2026 21:08	Jacob McDaniel	CPPg++14.2.0	Success	2,770
May 19, 2026 16:20	Elijah Kin	CPPclang++20.1.2	Success	10,232+5.13 RP
May 19, 2026 15:00	Elijah Kin	CPPclang++20.1.2	Error
May 19, 2026 14:46	Elijah Kin	CPPclang++20.1.2	Success	14,820
May 19, 2026 14:42	Elijah Kin	CPPclang++20.1.2	Success	14,791
May 19, 2026 14:29	Elijah Kin	CPPclang++20.1.2	Success	14,776
May 19, 2026 14:17	Elijah Kin	CPPg++14.2.0	Success	13,201
May 19, 2026 14:14	Elijah Kin	CPPclang++20.1.2	Success	10,286+71.46 RP
May 19, 2026 11:04	M-Rochat	CPPg++13.3.0	Success	55,077
May 19, 2026 09:07	Jacob McDaniel	CPPg++14.2.0	Success	2,761
May 19, 2026 08:56	Elijah Kin	CPPclang++20.1.2	Success	11,102+117.35 RP
May 19, 2026 08:53	Elijah Kin	CPPg++14.2.0	Success	34,137
May 19, 2026 08:52	Elijah Kin	CPPg++14.2.0	Success	34,283
May 19, 2026 08:34	Elijah Kin	CPPg++14.2.0	Success	16,208
May 19, 2026 08:29	Jacob McDaniel	CPPg++14.2.0	Success	2,740+7.98 RP
May 18, 2026 19:12	Jacob McDaniel	CPPg++14.2.0	Success	2,782
May 18, 2026 17:01	Jacob McDaniel	CPPg++14.2.0	Success	3,051
May 18, 2026 16:23	Jacob McDaniel	CPPg++14.2.0	Success	2,743+171.32 RP
May 18, 2026 08:09	Jacob McDaniel	CPPclang++15.0.7	Success	3,523
May 18, 2026 08:04	Jacob McDaniel	CPPclang++15.0.7	Success	2,919
May 18, 2026 07:22	Jacob McDaniel	CPPg++14.2.0	Success	2,809+50.32 RP
May 18, 2026 06:44	Jacob McDaniel	CPPg++14.2.0	Success	2,833+3.73 RP
May 18, 2026 06:29	Jacob McDaniel	CPPg++14.2.0	Success	2,846
May 18, 2026 06:20	Jacob McDaniel	CPPg++14.2.0	Success	2,836+24.69 RP
May 18, 2026 05:50	Jacob McDaniel	CPPg++14.2.0	Success	2,856+88.43 RP
May 18, 2026 05:42	Jacob McDaniel	CPPg++14.2.0	Success	3,318
May 18, 2026 04:31	M-Rochat	CPPclang++17.0.6	Success	4,522
May 17, 2026 23:22	M-Rochat	CPPclang++17.0.6	Success	4,681
May 17, 2026 22:47	Jacob McDaniel	CPPg++14.2.0	Success	2,937
May 17, 2026 22:33	Jacob McDaniel	CPPg++14.2.0	Success	2,930+185.08 RP
May 17, 2026 21:56	Jacob McDaniel	CPPg++14.2.0	Success	3,098+22.76 RP
May 17, 2026 21:39	Jacob McDaniel	CPPg++14.2.0	Success	3,296
May 17, 2026 18:46	Jacob McDaniel	CPPg++14.2.0	Success	3,120+131.04 RP
May 17, 2026 18:42	Jacob McDaniel	CPPg++14.2.0	Success	3,253+237.21 RP
May 17, 2026 18:34	Jacob McDaniel	CPPg++14.2.0	Success	3,525+43.58 RP
May 17, 2026 18:06	Jacob McDaniel	CPPg++14.2.0	Success	3,580+63.29 RP
May 17, 2026 17:45	Jacob McDaniel	CPPg++14.2.0	Success	3,663+22.91 RP
May 17, 2026 17:27	Jacob McDaniel	CPPg++14.2.0	Success	3,700

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