56 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			56 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
---
 | 
						||
id: 5900f4771000cf542c50ff8a
 | 
						||
challengeType: 5
 | 
						||
title: 'Problem 267: Billionaire'
 | 
						||
videoUrl: ''
 | 
						||
localeTitle: 问题267:亿万富翁
 | 
						||
---
 | 
						||
 | 
						||
## Description
 | 
						||
<section id="description">您将获得独特的投资机会。从1英镑的资本开始,你可以选择固定比例f来投注一个公平的硬币投掷1000次投掷。你的回报是对你的投注加倍,你失去了对尾巴的赌注。例如,如果f = 1/4,对于第一次投掷,你下注0.25英镑,如果头部出现你赢得0.5英镑,那么就有1.5英镑。然后你下注0.375英镑,如果第二次折腾是尾巴,你有1.125英镑。选择f以最大限度地提高在1,000次翻转后获得至少1,000,000,000英镑的机会,您成为亿万富翁的机会是多少?假设所有计算都是精确的(没有舍入),但是将答案四舍五入到小数点后面的12位数,形式为0.abcdefghijkl。 </section>
 | 
						||
 | 
						||
## Instructions
 | 
						||
<section id="instructions">
 | 
						||
</section>
 | 
						||
 | 
						||
## Tests
 | 
						||
<section id='tests'>
 | 
						||
 | 
						||
```yml
 | 
						||
tests:
 | 
						||
  - text: <code>euler267()</code>应返回0.999992836187。
 | 
						||
    testString: 'assert.strictEqual(euler267(), 0.999992836187, "<code>euler267()</code> should return 0.999992836187.");'
 | 
						||
 | 
						||
```
 | 
						||
 | 
						||
</section>
 | 
						||
 | 
						||
## Challenge Seed
 | 
						||
<section id='challengeSeed'>
 | 
						||
 | 
						||
<div id='js-seed'>
 | 
						||
 | 
						||
```js
 | 
						||
function euler267() {
 | 
						||
  // Good luck!
 | 
						||
  return true;
 | 
						||
}
 | 
						||
 | 
						||
euler267();
 | 
						||
 | 
						||
```
 | 
						||
 | 
						||
</div>
 | 
						||
 | 
						||
 | 
						||
 | 
						||
</section>
 | 
						||
 | 
						||
## Solution
 | 
						||
<section id='solution'>
 | 
						||
 | 
						||
```js
 | 
						||
// solution required
 | 
						||
```
 | 
						||
</section>
 |