45 lines
1.2 KiB
Markdown
45 lines
1.2 KiB
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 less than 100,000
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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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## Usage
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To run the application you'll need to have `elixir` installed. Assuming `elixir`
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is already installed, consult the following steps to start the application:
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```shell
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$ cd server
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$ mix deps.get
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$ iex -S mix
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```
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Now open a web browser and visit `http://localhost:8080`!
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