ruby , How to find the diagonal values of a natural square root number [closed]

## Question:

Tag: ruby

I'm trying to get the diagonal values of a square number. If I give the number 2, it should turn that into a square and give the diagonal values:

For 2

[0,1
2,3]


will give [[0,3],[1,2]]

or 3

[0,1,2
3,4,5
6,7,8]


will give [[0,4,8], [2,4,6]

or 4

[0 ,1 ,2 ,3
4 ,5 ,6 ,7
8 ,9 ,10,11
12,13,14,15]


will give [[0,5,10,15],[3,6,9,12]]

etc

def diagonal(2)

end
#=> [[0,3],[1,2]]


You should post something you've tried before. Anyway, here you go:

def diagonal(a)
[0.step(a**2,a+1).to_a, (a-1).step(a**2-a,a-1).to_a]
end

diagonal 2
#=> [[0, 3], [1, 2]]
diagonal 3
#=> [[0, 4, 8], [2, 4, 6]]
diagonal 4
#=> [[0, 5, 10, 15], [3, 6, 9, 12]]


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