79d9012432
* fix(curriculum): tests quotes * fix(curriculum): fill seed-teardown * fix(curriculum): fix tests and remove unneeded seed-teardown
95 lines
3.6 KiB
Markdown
95 lines
3.6 KiB
Markdown
---
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title: Greatest subsequential sum
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id: 5a23c84252665b21eecc7e84
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challengeType: 5
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---
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## Description
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<section id='description'>
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Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
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An empty subsequence is considered to have the sum of \( 0 \); thus if all elements are negative, the result must be the empty sequence.
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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>maximumSubsequence</code> should be a function.
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testString: assert(typeof maximumSubsequence=='function','<code>maximumSubsequence</code> should be a function.');
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- text: <code>maximumSubsequence([1,2,-1,3,10,-10])</code> should return an array.
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testString: assert(Array.isArray(maximumSubsequence([1,2,-1,3,10,-10])),'<code>maximumSubsequence([1,2,-1,3,10,-10])</code> should return an array.');
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- text: <code>maximumSubsequence([1,2,-1,3,10,-10])</code> should return <code>[ 1, 2, -1, 3, 10 ]</code>.
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testString: assert.deepEqual(maximumSubsequence([1,2,-1,3,10,-10]), [ 1, 2, -1, 3, 10 ],'<code>maximumSubsequence([1,2,-1,3,10,-10])</code> should return <code>[ 1, 2, -1, 3, 10 ]</code>.');
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- text: <code>maximumSubsequence([0, 8, 10, -2, -4, -1, -5, -3])</code> should return <code>[ 0, 8, 10 ]</code>.
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testString: assert.deepEqual(maximumSubsequence([0, 8, 10, -2, -4, -1, -5, -3]), [ 0, 8, 10 ],'<code>maximumSubsequence([0, 8, 10, -2, -4, -1, -5, -3])</code> should return <code>[ 0, 8, 10 ]</code>.');
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- text: <code>maximumSubsequence([9, 9, -10, 1])</code> should return <code>[ 9, 9 ]</code>.
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testString: assert.deepEqual(maximumSubsequence([9, 9, -10, 1]), [ 9, 9 ],'<code>maximumSubsequence([9, 9, -10, 1])</code> should return <code>[ 9, 9 ]</code>.');
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- text: <code>maximumSubsequence([7, 1, -5, -3, -8, 1]</code> should return <code>[ 7, 1 ]</code>.
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testString: assert.deepEqual(maximumSubsequence([7, 1, -5, -3, -8, 1]), [ 7, 1 ],'<code>maximumSubsequence([7, 1, -5, -3, -8, 1]</code> should return <code>[ 7, 1 ]</code>.');
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- text: <code>maximumSubsequence([-3, 6, -1, 4, -4, -6])</code> should return <code>[ 6, -1, 4 ]</code>.
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testString: assert.deepEqual(maximumSubsequence([-3, 6, -1, 4, -4, -6]), [ 6, -1, 4 ],'<code>maximumSubsequence([-3, 6, -1, 4, -4, -6])</code> should return <code>[ 6, -1, 4 ]</code>.');
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- text: <code>maximumSubsequence([-1, -2, 3, 5, 6, -2, -1, 4, -4, 2, -1])</code> should return <code>[ 3, 5, 6, -2, -1, 4 ]</code>.
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testString: assert.deepEqual(maximumSubsequence([-1, -2, 3, 5, 6, -2, -1, 4, -4, 2, -1]), [ 3, 5, 6, -2, -1, 4 ],'<code>maximumSubsequence([-1, -2, 3, 5, 6, -2, -1, 4, -4, 2, -1])</code> should return <code>[ 3, 5, 6, -2, -1, 4 ]</code>.');
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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 maximumSubsequence (population) {
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// Good luck!
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}
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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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function maximumSubsequence(population) {
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function sumValues(arr) {
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var result = 0;
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for (var i = 0, len = arr.length; i < len; i++) {
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result += arr[i];
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}
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return result;
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}
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var greatest;
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var maxValue = 0;
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var subsequence = [];
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for (var i = 0, len = population.length; i < len; i++) {
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for (var j = i; j <= len; j++) {
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var subsequence = population.slice(i, j);
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var value = sumValues(subsequence);
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if (value > maxValue) {
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maxValue = value;
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greatest = subsequence;
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};
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}
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}
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return greatest;
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}
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```
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</section>
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