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	1:20.1.2-0ubuntu1~24.04.2	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.
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	3.0.13-0ubuntu3.9	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.

Back to listApr 17, 2026 13:34

olliecrowScore: 18,245Success

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Run Statistics

#	Date	Score	Wall Time	CPU User	CPU System	Memory
1	Apr 18, 2026 11:14	5,285	33,478,979	12,196,000	1,016,000	2,371,584
2	Apr 18, 2026 11:14	5,326	30,744,026	10,243,000	3,072,000	2,506,752
3	Apr 18, 2026 11:14	5,468	30,851,940	9,465,000	4,206,000	2,301,952
4	Apr 17, 2026 23:23	7,553	47,540,919	14,907,000	3,975,000	2,510,848
5	Apr 17, 2026 23:23	7,584	41,336,703	17,962,000	997,000	2,506,752
6	Apr 17, 2026 23:23	7,793	38,286,343	12,305,000	7,178,000	2,506,752
7	Apr 17, 2026 20:43	16,126	63,064,307	38,300,000	2,015,000	2,322,432
8	Apr 17, 2026 20:43	16,141	62,548,835	38,335,000	2,017,000	2,392,064
9	Apr 17, 2026 20:43	16,564	62,940,130	39,391,000	2,020,000	2,379,776
10	Apr 17, 2026 18:40	17,410	69,417,098	42,512,000	1,012,000	2,326,528
11	Apr 17, 2026 18:40	17,540	71,017,671	40,860,000	2,989,000	2,392,064
12	Apr 17, 2026 18:40	17,555	68,752,155	40,896,000	2,992,000	2,379,776
13	Apr 17, 2026 19:28	18,202	70,728,308	44,495,000	1,011,000	2,265,088
14	Apr 17, 2026 19:28	18,245	68,952,666	43,585,000	2,027,000	2,273,280
15	Apr 17, 2026 19:28	18,341	70,170,917	44,857,000	996,000	2,519,040
16	Apr 17, 2026 19:34	18,349	77,115,074	44,876,000	997,000	2,428,928
17	Apr 17, 2026 19:34	18,360	75,882,822	44,903,000	997,000	2,404,352
18	Apr 17, 2026 19:34	18,362	75,701,280	42,912,000	2,993,000	2,265,088
19	Apr 17, 2026 19:38	18,840	68,681,170	43,093,000	4,008,000	2,269,184
20	Apr 17, 2026 19:38	18,872	70,281,223	43,165,000	4,015,000	2,265,088
21	Apr 17, 2026 19:38	18,964	70,816,213	45,392,000	2,017,000	2,265,088
22	Apr 9, 2026 03:25	19,861	74,599,434	47,627,000	2,026,000	2,293,760
23	Apr 9, 2026 03:25	19,880	87,441,712	47,673,000	2,028,000	2,334,720
24	Apr 9, 2026 03:25	19,895	82,620,772	45,678,000	4,060,000	2,293,760
25	Apr 17, 2026 13:34	20,601	74,334,776	49,483,000	2,019,000	2,375,680
26	Apr 17, 2026 13:34	20,773	79,427,713	49,936,000	1,997,000	2,273,280
27	Apr 17, 2026 13:34	20,886	76,743,396	48,200,000	4,016,000	2,326,528

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