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exercism fetch php difference-of-squares

Difference Of Squares

Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.

The square of the sum of the first ten natural numbers is (1 + 2 + ... + 10)² = 55² = 3025.

The sum of the squares of the first ten natural numbers is 1² + 2² + ... + 10² = 385.

Hence the difference between the square of the sum of the first ten natural numbers and the sum of the squares of the first ten natural numbers is 3025 - 385 = 2640.

Making the Test Suite Pass

  1. Get PHPUnit.

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    % wget --no-check-certificate https://phar.phpunit.de/phpunit.phar
    % chmod +x phpunit.phar
    
  2. Execute the tests for an assignment.

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    % phpunit.phar wordy/wordy_test.php
    

Source

Problem 6 at Project Euler http://projecteuler.net/problem=6

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.