A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.

Some attributes of a list comprehension are:

 They should be distinct from (nested) for loops and the use of map and filter functions within the syntax of the language.
 They should return either a list or an iterator (something that returns successive members of a collection, in order).
 The syntax has parts corresponding to that of set-builder notation. 


Task

Write a list comprehension that builds the list of all Pythagorean triples with elements between   1   and   n.

If the language has multiple ways for expressing such a construct (for example, direct list comprehensions and generators), write one example for each.




Module ListComp
    Sub Main()
        Dim ts = From a In Enumerable.Range(1, 20) _
                 From b In Enumerable.Range(a, 21 - a) _
                 From c In Enumerable.Range(b, 21 - b) _
                 Where a * a + b * b = c * c _
                 Select New With { a, b, c }
 
        For Each t In ts
            System.Console.WriteLine("{0}, {1}, {2}", t.a, t.b, t.c)
        Next
    End Sub
End Module