74 lines
1.6 KiB
Markdown
74 lines
1.6 KiB
Markdown
---
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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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forumTopicId: 301778
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---
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## Description
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<section id='description'>
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Looking at the table below, it is easy to verify that the maximum possible sum of adjacent numbers in any direction (horizontal, vertical, diagonal or anti-diagonal) is 16 (= 8 + 7 + 1).
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−25329−6513273−18−4 8
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Now, let us repeat the search, but on a much larger scale:
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First, generate four million pseudo-random numbers using a specific form of what is known as a "Lagged Fibonacci Generator":
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For 1 ≤ k ≤ 55, sk = [100003 − 200003k + 300007k3] (modulo 1000000) − 500000.
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For 56 ≤ k ≤ 4000000, sk = [sk−24 + sk−55 + 1000000] (modulo 1000000) − 500000.
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Thus, s10 = −393027 and s100 = 86613.
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The terms of s are then arranged in a 2000×2000 table, using the first 2000 numbers to fill the first row (sequentially), the next 2000 numbers to fill the second row, and so on.
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Finally, find the greatest sum of (any number of) adjacent entries in any direction (horizontal, vertical, diagonal or anti-diagonal).
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</section>
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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> should return 52852124.
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testString: assert.strictEqual(euler149(), 52852124);
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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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