93 lines
2.9 KiB
Markdown
93 lines
2.9 KiB
Markdown
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---
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title: Greatest subsequential sum
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id: 5a23c84252665b21eecc7e84
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challengeType: 5
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forumTopicId: 302278
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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');
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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 ])));
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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 ]);
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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 ]);
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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 ]);
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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 ]);
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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 ]);
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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 ]);
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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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}
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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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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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