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Work on primes to be performed. dump has been created to avoid recalculation each time. But I 'll spend some time working on sieves. Signed-off-by: Julien Lengrand-Lambert <julien@lengrand.fr>
44 lines
1.1 KiB
Python
44 lines
1.1 KiB
Python
#!/usr/bin/env python
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"""
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##---
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# Julien Lengrand-Lambert
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#Created on : Thu Jan 19 10:12:06 CET 2012
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#
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# DESCRIPTION : Solves problem 36 of Project Euler
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The decimal number, 585 = 1001001001 (binary), is palindromic in both bases.
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Find the sum of all numbers, less than one million, which are palindromic in base 10 and base 2.
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(Please note that the palindromic number, in either base, may not include leading zeros.)
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##---
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"""
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def is_palindrom(number):
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"""
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Returns True if a number is a palindrom, False otherwise
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"""
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return str(number)[::-1] == str(number)
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def dec2strbin(number):
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"""
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Returns a string value, corresponding to number expressed in base 2.
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"""
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return bin(number)[2:]
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def sum_palindroms(max):
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"""
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Returns the sum, less than max, which are palindromic in both 10 and 2 bases.
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"""
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sump = 0
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curr = 0
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while (curr < max):
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if (is_palindrom(curr) and is_palindrom(dec2strbin(curr))):
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sump += curr
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curr += 1
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return sump
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if __name__ == '__main__' :
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print "Answer is : %d" % (sum_palindroms(1000000))
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