mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-24 13:31:07 +00:00
f7ac8b5ed0
* Added doctest and more explanation about Dijkstra execution. * tests were not passing with python2 due to missing __init__.py file at number_theory folder * Removed the dot at the beginning of the imported modules names because 'python3 -m doctest -v data_structures/hashing/*.py' and 'python3 -m doctest -v data_structures/stacks/*.py' were failing not finding hash_table.py and stack.py modules. * Moved global code to main scope and added doctest for project euler problems 1 to 14. * Added test case for negative input. * Changed N variable to do not use end of line scape because in case there is a space after it the script will break making it much more error prone. * Added problems description and doctests to the ones that were missing. Limited line length to 79 and executed python black over all scripts. * Changed the way files are loaded to support pytest call. * Added __init__.py to problems to make them modules and allow pytest execution. * Added project_euler folder to test units execution * Changed 'os.path.split(os.path.realpath(__file__))' to 'os.path.dirname()' * Added Burrows-Wheeler transform algorithm. * Added changes suggested by cclauss * Fixes for issue 'Fix the LGTM issues #1024'. * Added doctest for different parameter types and negative values. * Fixed doctest issue added at last commit. * Commented doctest that were causing slowness at Travis. * Added comment with the reason for some doctest commented. * pytest --ignore
67 lines
1.4 KiB
Python
67 lines
1.4 KiB
Python
"""
|
|
Highly divisible triangular numbers
|
|
Problem 12
|
|
The sequence of triangle numbers is generated by adding the natural numbers. So
|
|
the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. The first ten
|
|
terms would be:
|
|
|
|
1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
|
|
|
|
Let us list the factors of the first seven triangle numbers:
|
|
|
|
1: 1
|
|
3: 1,3
|
|
6: 1,2,3,6
|
|
10: 1,2,5,10
|
|
15: 1,3,5,15
|
|
21: 1,3,7,21
|
|
28: 1,2,4,7,14,28
|
|
We can see that 28 is the first triangle number to have over five divisors.
|
|
|
|
What is the value of the first triangle number to have over five hundred
|
|
divisors?
|
|
"""
|
|
from __future__ import print_function
|
|
from math import sqrt
|
|
|
|
try:
|
|
xrange # Python 2
|
|
except NameError:
|
|
xrange = range # Python 3
|
|
|
|
|
|
def count_divisors(n):
|
|
nDivisors = 0
|
|
for i in xrange(1, int(sqrt(n)) + 1):
|
|
if n % i == 0:
|
|
nDivisors += 2
|
|
# check if n is perfect square
|
|
if n ** 0.5 == int(n ** 0.5):
|
|
nDivisors -= 1
|
|
return nDivisors
|
|
|
|
|
|
def solution():
|
|
"""Returns the value of the first triangle number to have over five hundred
|
|
divisors.
|
|
|
|
# The code below has been commented due to slow execution affecting Travis.
|
|
# >>> solution()
|
|
# 76576500
|
|
"""
|
|
tNum = 1
|
|
i = 1
|
|
|
|
while True:
|
|
i += 1
|
|
tNum += i
|
|
|
|
if count_divisors(tNum) > 500:
|
|
break
|
|
|
|
return tNum
|
|
|
|
|
|
if __name__ == "__main__":
|
|
print(solution())
|