Python/project_euler/problem_01/sol3.py
2018-10-19 17:14:25 -05:00

51 lines
900 B
Python

from __future__ import print_function
'''
Problem Statement:
If we list all the natural numbers below 10 that are multiples of 3 or 5,
we get 3,5,6 and 9. The sum of these multiples is 23.
Find the sum of all the multiples of 3 or 5 below N.
'''
'''
This solution is based on the pattern that the successive numbers in the series follow: 0+3,+2,+1,+3,+1,+2,+3.
'''
try:
raw_input # Python 2
except NameError:
raw_input = input # Python 3
n = int(raw_input().strip())
sum=0
num=0
while(1):
num+=3
if(num>=n):
break
sum+=num
num+=2
if(num>=n):
break
sum+=num
num+=1
if(num>=n):
break
sum+=num
num+=3
if(num>=n):
break
sum+=num
num+=1
if(num>=n):
break
sum+=num
num+=2
if(num>=n):
break
sum+=num
num+=3
if(num>=n):
break
sum+=num
print(sum);