I'm currently learning Haskell and am an absolute beginner when it comes to FP.

Right now I'm trying different stuff with list comprehensions.

```
 listComprehension  = [(a,b,c) | a <- xs, b <- xs, c <- ys, even c, c == a+b] ++
                      [(a,b,c) | a <- xs, b <- xs, c <- ys, even c, c == a-b]
                      where xs = [1..4]; ys = [(-100)..100]

```

So why not say:

```
 listComprehension  = [(a,b,c) | a <- xs, b <- xs, c <- ys, even c, c == a+b || c == a-b]
                      where xs = [1..4]; ys = [(-100)..100]

```

?

I want the elements to be ordered exactly like my first example.
I want all elements where c = a+b and then all elements where c = a-b.

Notice that in my 2nd code the order is not what I would like to have. I can't seem to figure out how I order things in a list comprehension, specially when I have tuples..

Thank you!