source code
# The Computer Language Benchmarks Game
# https://salsa.debian.org/benchmarksgame-team/benchmarksgame/
#
# contributed by Antoine Pitrou
# modified by Dominique Wahli and Daniel Nanz
# modified by Joerg Baumann
import sys
import multiprocessing as mp
def make_tree(d):
if d > 0:
d -= 1
return (make_tree(d), make_tree(d))
return (None, None)
def check_tree(node):
(l, r) = node
if l is None:
return 1
else:
return 1 + check_tree(l) + check_tree(r)
def make_check(itde, make=make_tree, check=check_tree):
i, d = itde
return check(make(d))
def get_argchunks(i, d, chunksize=5000):
assert chunksize % 2 == 0
chunk = []
for k in range(1, i + 1):
chunk.extend([(k, d)])
if len(chunk) == chunksize:
yield chunk
chunk = []
if len(chunk) > 0:
yield chunk
def main(n, min_depth=4):
max_depth = max(min_depth + 2, n)
stretch_depth = max_depth + 1
if mp.cpu_count() > 1:
pool = mp.Pool()
chunkmap = pool.map
else:
chunkmap = map
print('stretch tree of depth {0}\t check: {1}'.format(
stretch_depth, make_check((0, stretch_depth))))
long_lived_tree = make_tree(max_depth)
mmd = max_depth + min_depth
for d in range(min_depth, stretch_depth, 2):
i = 2 ** (mmd - d)
cs = 0
for argchunk in get_argchunks(i,d):
cs += sum(chunkmap(make_check, argchunk))
print('{0}\t trees of depth {1}\t check: {2}'.format(i, d, cs))
print('long lived tree of depth {0}\t check: {1}'.format(
max_depth, check_tree(long_lived_tree)))
if __name__ == '__main__':
main(int(sys.argv[1]))
notes, command-line, and program output
NOTES:
64-bit Ubuntu quad core
Python 3.8.0
Mon, 11 May 2020 00:32:55 GMT
MAKE:
mv binarytrees.python3 binarytrees.py
mypy .
Success: no issues found in 1 source file
5.80s to complete and log all make actions
COMMAND LINE:
/opt/src/Python-3.8.0/bin/python3 -OO binarytrees.py 21
PROGRAM OUTPUT:
stretch tree of depth 22 check: 8388607
2097152 trees of depth 4 check: 65011712
524288 trees of depth 6 check: 66584576
131072 trees of depth 8 check: 66977792
32768 trees of depth 10 check: 67076096
8192 trees of depth 12 check: 67100672
2048 trees of depth 14 check: 67106816
512 trees of depth 16 check: 67108352
128 trees of depth 18 check: 67108736
32 trees of depth 20 check: 67108832
long lived tree of depth 21 check: 4194303