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id	challengeType	title
5900f3901000cf542c50fea3	5	Problem 36: Double-base palindromes

Description

The decimal number, 585 = 10010010012 (binary), is palindromic in both bases. Find the sum of all numbers, less than n, whereas 1000 <= n <= 1000000, which are palindromic in base 10 and base 2. (Please note that the palindromic number, in either base, may not include leading zeros.)

Instructions

Tests

tests:
  - text: <code>doubleBasePalindromes(1000)</code> should return 1772.
    testString: assert(doubleBasePalindromes(1000) == 1772, '<code>doubleBasePalindromes(1000)</code> should return 1772.');
  - text: <code>doubleBasePalindromes(50000)</code> should return 105795.
    testString: assert(doubleBasePalindromes(50000) == 105795, '<code>doubleBasePalindromes(50000)</code> should return 105795.');
  - text: <code>doubleBasePalindromes(500000)</code> should return 286602.
    testString: assert(doubleBasePalindromes(500000) == 286602, '<code>doubleBasePalindromes(500000)</code> should return 286602.');
  - text: <code>doubleBasePalindromes(1000000)</code> should return 872187.
    testString: assert(doubleBasePalindromes(1000000) == 872187, '<code>doubleBasePalindromes(1000000)</code> should return 872187.');

Challenge Seed

function doubleBasePalindromes(n) {
  // Good luck!
  return n;
}

doubleBasePalindromes(1000000);

Solution

// solution required

1.6 KiB Raw Blame History