49 lines
1.5 KiB
Markdown
49 lines
1.5 KiB
Markdown
---
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id: 5900f4361000cf542c50ff48
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title: 'Problem 201: Subsets with a unique sum'
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challengeType: 5
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forumTopicId: 301841
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dashedName: problem-201-subsets-with-a-unique-sum
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---
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# --description--
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For any set A of numbers, let sum(A) be the sum of the elements of A.
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Consider the set B = {1,3,6,8,10,11}. There are 20 subsets of B containing three elements, and their sums are:
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sum({1,3,6}) = 10, sum({1,3,8}) = 12, sum({1,3,10}) = 14, sum({1,3,11}) = 15, sum({1,6,8}) = 15, sum({1,6,10}) = 17, sum({1,6,11}) = 18, sum({1,8,10}) = 19, sum({1,8,11}) = 20, sum({1,10,11}) = 22, sum({3,6,8}) = 17, sum({3,6,10}) = 19, sum({3,6,11}) = 20, sum({3,8,10}) = 21, sum({3,8,11}) = 22, sum({3,10,11}) = 24, sum({6,8,10}) = 24, sum({6,8,11}) = 25, sum({6,10,11}) = 27, sum({8,10,11}) = 29.
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Some of these sums occur more than once, others are unique. For a set A, let U(A,k) be the set of unique sums of k-element subsets of A, in our example we find U(B,3) = {10,12,14,18,21,25,27,29} and sum(U(B,3)) = 156.
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Now consider the 100-element set S = {12, 22, ... , 1002}. S has 100891344545564193334812497256 50-element subsets.
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Determine the sum of all integers which are the sum of exactly one of the 50-element subsets of S, i.e. find sum(U(S,50)).
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# --hints--
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`euler201()` should return 115039000.
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```js
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assert.strictEqual(euler201(), 115039000);
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```
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# --seed--
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## --seed-contents--
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```js
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function euler201() {
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return true;
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}
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euler201();
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```
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# --solutions--
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```js
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// solution required
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```
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