---
id: 5900f3941000cf542c50fea7
challengeType: 5
title: 'Problem 40: Champernowne"s constant'
videoUrl: ''
localeTitle: 'Problema 40: constante de Champernowne'
---

## Description
<section id="description"> Uma fração decimal irracional é criado pela concatenação dos inteiros positivos: <span style="display: block; text-align: center;">0,12345678910 <b style="color: red;">1</b> 112131415161718192021 ...</span> Pode ser visto que o <sup>12º</sup> dígito da parte fracionária é 1. Se <i>d <sub>n</sub></i> representa o <i>n</i> <sup>th</sup> dígitos da parte fracionária, encontrar o valor da seguinte expressão. <span style="display: block; text-align: center;">d <sub>1</sub> × d <sub>10</sub> × d <sub>100</sub> × d <sub>1000</sub> × d <sub>10000</sub> × d <sub>100000</sub> × d <sub>1000000</sub></span> </section>

## Instructions
<section id="instructions">
</section>

## Tests
<section id='tests'>

```yml
tests:
  - text: <code>champernownesConstant(100)</code> deve retornar 5.
    testString: 'assert.strictEqual(champernownesConstant(100), 5, "<code>champernownesConstant(100)</code> should return 5.");'
  - text: <code>champernownesConstant(1000)</code> deve retornar 15.
    testString: 'assert.strictEqual(champernownesConstant(1000), 15, "<code>champernownesConstant(1000)</code> should return 15.");'
  - text: <code>champernownesConstant(1000000)</code> deve retornar 210.
    testString: 'assert.strictEqual(champernownesConstant(1000000), 210, "<code>champernownesConstant(1000000)</code> should return 210.");'

```

</section>

## Challenge Seed
<section id='challengeSeed'>

<div id='js-seed'>

```js
function champernownesConstant(n) {
  // Good luck!
  return true;
}

champernownesConstant(100);

```

</div>



</section>

## Solution
<section id='solution'>

```js
// solution required
```
</section>