hgupta / magic-squares-ruby

Magic Square solver in Ruby

Magic Squares problem

A magic square of size N is a square with the numbers from 1 to N ** 2 arranged so that each row, column, and the two long diagonals have the same sum. For example, a magic square for N = 5 could be:

+------------------------+
| 15 |  8 |  1 | 24 | 17 |
+------------------------+
| 16 | 14 |  7 |  5 | 23 |
+------------------------+
| 22 | 20 | 13 |  6 |  4 |
+------------------------+
|  3 | 21 | 19 | 12 | 10 |
+------------------------+
|  9 |  2 | 25 | 18 | 11 |
+------------------------+

In this case the magic sum is 65. All rows, columns, and both diagonals add up to that.

Files

1. magic_square.rb - Actual code
2. test_magic_square.rb - test cases for orders 3, 4, 6 and 5

Usage

To execute code:

> ruby magic_square.rb <order as integer value>

Examples:
> ruby magic_square.rb 3
> ruby magic_square.rb 4
> ruby magic_square.rb 6

To run test cases:

> ruby test_magic_square.rb

Note

Ruby version 2.1.5 used for testing.