Python/project_euler/problem_10/sol1.py

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"""
Problem Statement:
The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
Find the sum of all the primes below two million.
"""
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from __future__ import print_function
from math import sqrt
try:
raw_input # Python 2
except NameError:
raw_input = input # Python 3
try:
xrange # Python 2
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except NameError:
xrange = range # Python 3
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def is_prime(n):
for i in xrange(2, int(sqrt(n)) + 1):
if n % i == 0:
return False
return True
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def sum_of_primes(n):
if n > 2:
sumOfPrimes = 2
else:
return 0
for i in xrange(3, n, 2):
if is_prime(i):
sumOfPrimes += i
return sumOfPrimes
def solution(n):
"""Returns the sum of all the primes below n.
Commented doctests that were causing slowness at Travis. (#1039) * 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
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# The code below has been commented due to slow execution affecting Travis.
# >>> solution(2000000)
# 142913828922
>>> solution(1000)
76127
>>> solution(5000)
1548136
>>> solution(10000)
5736396
>>> solution(7)
10
"""
return sum_of_primes(n)
if __name__ == "__main__":
print(solution(int(raw_input().strip())))