Python/project_euler/problem_36/sol1.py

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"""
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Double-base palindromes
Problem 36
The decimal number, 585 = 10010010012 (binary), is palindromic in both bases.
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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def is_palindrome(n):
n = str(n)
if n == n[::-1]:
return True
else:
return False
def solution(n):
"""Return the sum of all numbers, less than n , which are palindromic in
base 10 and base 2.
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>>> solution(1000000)
872187
>>> solution(500000)
286602
>>> solution(100000)
286602
>>> solution(1000)
1772
>>> solution(100)
157
>>> solution(10)
25
>>> solution(2)
1
>>> solution(1)
0
"""
total = 0
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for i in range(1, n):
if is_palindrome(i) and is_palindrome(bin(i).split("b")[1]):
total += i
return total
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if __name__ == "__main__":
print(solution(int(str(input().strip()))))