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											2018-10-10 18:03:03 -04:00
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							|  |  |  |  | id: 5900f4481000cf542c50ff5a | 
					
						
							|  |  |  |  | challengeType: 5 | 
					
						
							|  |  |  |  | title: 'Problem 219: Skew-cost coding' | 
					
						
							|  |  |  |  | videoUrl: '' | 
					
						
							|  |  |  |  | localeTitle: 问题219:偏差成本编码 | 
					
						
							|  |  |  |  | --- | 
					
						
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							|  |  |  |  | ## Description
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							|  |  |  |  | <section id="description">设A和B为位串(0和1的序列)。如果A等于B的最左边长度(A)位,则A被称为B的前缀。例如,00110是001101001的前缀,但不是00111或100110的前缀。 <p>大小为n的无前缀代码是n个不同位串的集合,因此没有字符串是任何其他字符串的前缀。例如,这是一个大小为6的无前缀代码: </p><p> 0000,0001,001,01,10,11 </p><p>现在假设发送'0'位需要一分钱,而传输'1'需要4便士。然后,上面显示的无前缀代码的总成本是35便士,这恰好是所讨论的偏斜定价方案可能最便宜的。简而言之,我们写Cost(6)= 35。 </p><p>什么是成本(109)? </p></section> | 
					
						
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							|  |  |  |  | ## Instructions
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							|  |  |  |  | <section id="instructions"> | 
					
						
							|  |  |  |  | </section> | 
					
						
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							|  |  |  |  | ## Tests
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							|  |  |  |  | <section id='tests'> | 
					
						
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							|  |  |  |  | ```yml | 
					
						
							|  |  |  |  | tests: | 
					
						
							|  |  |  |  |   - text: <code>euler219()</code>应返回64564225042。 | 
					
						
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										 |  |  |  |     testString: assert.strictEqual(euler219(), 64564225042); | 
					
						
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							|  |  |  |  | ``` | 
					
						
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							|  |  |  |  | </section> | 
					
						
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							|  |  |  |  | ## Challenge Seed
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							|  |  |  |  | <section id='challengeSeed'> | 
					
						
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							|  |  |  |  | <div id='js-seed'> | 
					
						
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | function euler219() { | 
					
						
							|  |  |  |  |   // Good luck! | 
					
						
							|  |  |  |  |   return true; | 
					
						
							|  |  |  |  | } | 
					
						
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							|  |  |  |  | euler219(); | 
					
						
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							|  |  |  |  | ``` | 
					
						
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							|  |  |  |  | </div> | 
					
						
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							|  |  |  |  | </section> | 
					
						
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							|  |  |  |  | ## Solution
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							|  |  |  |  | <section id='solution'> | 
					
						
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | // solution required | 
					
						
							|  |  |  |  | ``` | 
					
						
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							|  |  |  |  | /section> |