""" Project Euler Problem 36 https://projecteuler.net/problem=36 Problem Statement: 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. (Please note that the palindromic number, in either base, may not include leading zeros.) """ from __future__ import annotations def is_palindrome(n: int | str) -> bool: """ Return true if the input n is a palindrome. Otherwise return false. n can be an integer or a string. >>> is_palindrome(909) True >>> is_palindrome(908) False >>> is_palindrome('10101') True >>> is_palindrome('10111') False """ n = str(n) return True if n == n[::-1] else False def solution(n: int = 1000000): """Return the sum of all numbers, less than n , which are palindromic in base 10 and base 2. >>> 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 for i in range(1, n): if is_palindrome(i) and is_palindrome(bin(i).split("b")[1]): total += i return total if __name__ == "__main__": print(solution(int(str(input().strip()))))