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DifferenceOfSquares.php 2f0277f2f0 14: Difference of squares. 3 weeks ago
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README.md

Difference of Squares

Welcome to Difference of Squares on Exercism's PHP Track. If you need help running the tests or submitting your code, check out HELP.md.

Instructions

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.

You are not expected to discover an efficient solution to this yourself from first principles; research is allowed, indeed, encouraged. Finding the best algorithm for the problem is a key skill in software engineering.

Source

Contributed to by

Based on

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