31 lines
902 B
Markdown
31 lines
902 B
Markdown
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# Semiprimes Service
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## Introduction
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A **composite** is a number containing at least two prime factors. For example:
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```
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15 = 3 × 5
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9 = 3 × 3
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12 = 2 × 2 × 3
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```
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There are ten composites below thirty containing precisely two, not necessarily
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distinct, prime factors: `4, 6, 9, 10, 14, 15, 21, 22, 25, 26`. Let’s call such
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numbers *Semiprimes*.
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## Task
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- Write a module which provides a function to tell whether a given number, `N`,
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is a semiprime. `N` will be 10^5.
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- Please implement an API (RESTful or GraphQL) to factor a given number into two
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prime numbers if it’s a semiprime, otherwise, return an error message.
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## Stretch Goals
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- Handle the invalid inputs.
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- Support batch requests: i.e. users could provide 100 numbers, and the API
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return the answer for all.
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- Considering this module will be used by a long running service, could you
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optimize it to give answers faster?
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