freeCodeCamp/curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-113-non-bouncy-numb...

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id title challengeType forumTopicId dashedName
5900f3dd1000cf542c50fef0 Problem 113: Non-bouncy numbers 5 301739 problem-113-non-bouncy-numbers

--description--

Working from left-to-right if no digit is exceeded by the digit to its left it is called an increasing number; for example, 134468.

Similarly if no digit is exceeded by the digit to its right it is called a decreasing number; for example, 66420.

We shall call a positive integer that is neither increasing nor decreasing a "bouncy" number; for example, 155349.

As n increases, the proportion of bouncy numbers below n increases such that there are only 12951 numbers below one-million that are not bouncy and only 277032 non-bouncy numbers below 1010.

How many numbers below a googol (10100) are not bouncy?

--hints--

euler113() should return 51161058134250.

assert.strictEqual(euler113(), 51161058134250);

--seed--

--seed-contents--

function euler113() {

  return true;
}

euler113();

--solutions--

// solution required