Each table row shows performance measurements for this program with a particular command-line input value N.
N | CPU secs | Elapsed secs | Memory KB | Code B | ≈ CPU Load |
---|---|---|---|---|---|
10 | 7.68 | 1.04 | 102,820 | 1069 | 86% 94% 95% 92% 96% 91% 93% 95% |
Read the ↓ make, command line, and program output logs to see how this program was run.
Read benchmark to see what this program should do.
# The Computer Language Benchmarks Game # http://benchmarksgame.alioth.debian.org/ # # contributed by Joerg Baumann # many thanks to Oleg Mazurov for his helpful description from sys import argv from math import factorial from multiprocessing import cpu_count, Pool from itertools import islice, starmap def permutations(n, start, size): p = bytearray(range(n)) count = bytearray(n) remainder = start for v in range(n - 1, 0, -1): count[v], remainder = divmod(remainder, factorial(v)) for _ in range(count[v]): p[:v], p[v] = p[1:v + 1], p[0] assert(count[1] == 0) assert(size < 2 or (size % 2 == 0)) if size < 2: yield p[:] else: rotation_swaps = [None] * n for i in range(1, n): r = list(range(n)) for v in range(1, i + 1): r[:v], r[v] = r[1:v + 1], r[0] swaps = [] for dst, src in enumerate(r): if dst != src: swaps.append((dst, src)) rotation_swaps[i] = tuple(swaps) while True: yield p[:] p[0], p[1] = p[1], p[0] yield p[:] i = 2 while count[i] >= i: count[i] = 0 i += 1 else: count[i] += 1 t = p[:] for dst, src in rotation_swaps[i]: p[dst] = t[src] def alternating_flips_generator(n, start, size): maximum_flips = 0 alternating_factor = 1 for permutation in islice(permutations(n, start, size), size): first = permutation[0] if first: flips_count = 1 while True: permutation[:first + 1] = permutation[first::-1] first = permutation[0] if not first: break flips_count += 1 if maximum_flips < flips_count: maximum_flips = flips_count yield flips_count * alternating_factor else: yield 0 alternating_factor = -alternating_factor yield maximum_flips def task(n, start, size): alternating_flips = alternating_flips_generator(n, start, size) return sum(islice(alternating_flips, size)), next(alternating_flips) def fannkuch(n): if n < 0: for data in islice(permutations(-n, 0, factorial(-n)), factorial(-n)): print(''.join(map(lambda n: str(n + 1), data))) else: assert(n > 0) task_count = cpu_count() total = factorial(n) task_size = (total + task_count - 1) // task_count if task_size < 20000: task_size = total task_count = 1 assert(task_size % 2 == 0) task_args = [(n, i * task_size, task_size) for i in range(task_count)] if task_count > 1: with Pool() as pool: checksums, maximums = zip(*pool.starmap(task, task_args)) else: checksums, maximums = zip(*starmap(task, task_args)) checksum, maximum = sum(checksums), max(maximums) print("{0}\nPfannkuchen({1}) = {2}".format(checksum, n, maximum)) if __name__ == "__main__": fannkuch(int(argv[1]))
Sun, 23 Apr 2023 09:02:00 GMT MAKE: make[1]: Vstupuje se do adresáře „/home/dundee/work/pybenchmarks/bencher/tmp/fannkuchredux/tmp“ nuitka3 --remove-output fannkuchredux.nuitka-4.nuitka Nuitka-Options:INFO: Used command line options: --remove-output fannkuchredux.nuitka-4.nuitka Nuitka-Options:WARNING: You did not specify to follow or include anything but main program. Check options and make sure that is intended. Nuitka:INFO: Starting Python compilation with Nuitka '1.5' on Python '3.10' commercial grade 'not installed'. Nuitka-Plugins:INFO: multiprocessing: Injecting pre-module load code for module 'multiprocessing': Nuitka-Plugins:INFO: multiprocessing: Monkey patching "multiprocessing" load environment. Nuitka-Plugins:INFO: multiprocessing: Injecting post-module load code for module 'multiprocessing': Nuitka-Plugins:INFO: multiprocessing: Monkey patching "multiprocessing" for compiled methods. Nuitka:INFO: Completed Python level compilation and optimization. Nuitka:INFO: Generating source code for C backend compiler. Nuitka:INFO: Running data composer tool for optimal constant value handling. Nuitka:INFO: Running C compilation via Scons. Nuitka-Scons:INFO: Backend C compiler: gcc (gcc). Nuitka-Scons:INFO: Backend linking program with 10 files (no progress information available). Nuitka-Scons:WARNING: You are not using ccache. Nuitka:INFO: Removing build directory 'fannkuchredux.nuitka-4.nuitka.build'. Nuitka:INFO: Successfully created 'fannkuchredux.nuitka-4.nuitka.bin'. cp fannkuchredux.nuitka-4.nuitka.bin fannkuchredux.nuitka-4.nuitka_run make[1]: Opouští se adresář „/home/dundee/work/pybenchmarks/bencher/tmp/fannkuchredux/tmp“ 21.07s to complete and log all make actions COMMAND LINE: ./fannkuchredux.nuitka-4.nuitka_run 10 PROGRAM OUTPUT: 73196 Pfannkuchen(10) = 38