2018-10-10 18:03:03 -04:00
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---
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id: 5900f4021000cf542c50ff13
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challengeType: 5
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title: 'Problem 149: Searching for a maximum-sum subsequence'
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videoUrl: ''
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localeTitle: 问题149:搜索最大和子序列
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---
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## Description
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2020-02-18 01:40:55 +09:00
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<section id="description">
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查看下表,可以很容易地验证任意方向(水平,垂直,对角或反对角)上相邻数字的最大和为16(= 8 + 7 + 1)。
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−25329−6513273−18−4 8
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现在,让我们重复搜索,但范围更大:
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首先,使用称为“滞后斐波那契生成器”的特定形式生成四百万个伪随机数:
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对于1≤k≤55,sk = [100003 − 200003k + 300007k3](模1000000)− 500000。
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对于56≤k≤4000000,sk = [sk-24 + sk-55 + 1000000](模1000000)− 500000。
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因此,s10 = -393027,s100 = 86613。
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然后,将s的项排列在2000×2000表中,使用前2000个数字(顺序)填充第一行,使用后2000个数字填充第二行,依此类推。
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最后,在任何方向(水平,垂直,对角线或反对角线)上找到(任意数量)相邻项的最大和。
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</section>
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2018-10-10 18:03:03 -04:00
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## Instructions
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<section id="instructions">
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>euler149()</code>应该返回52852124。
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2020-02-18 01:40:55 +09:00
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testString: assert.strictEqual(euler149(), 52852124);
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2018-10-10 18:03:03 -04:00
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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
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function euler149() {
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// Good luck!
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return true;
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}
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euler149();
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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
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// solution required
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```
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</section>
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