sorting failed error

[maarten van damme]

About float not beeing deterministic, would this behavior also exist
when I use doubles? I've changed everything to use doubles now and the
same error comes up.

My sorting function used < so I guess it can never return on (a,b)
when (b,a) was true. But on the other hand, it can return false twice.
Is it antisymmetric then?

I have a struct that encapsulates an array. Shouldn't that struct get
passed by value? Because right now the array inside that struct get's
passed by reference. How can I circumvent this?

I thought I had the problem at the line
city[] cities=victim.dna

I later on modified cities so it should've been victim.dna.dpu. This
didn't solve the problem however...