I want to show that there exists $c>0$ constant s.t for any tournament on $n$ vertices there are two disjoint subsets A and B s.t:
$ e(A,B)-e(B,A) \geq c n^{\frac{3}{2}}$
I know of the theorem that says that for $\min \{FIT(T,\sigma) , \sigma \in S_n \} \leq O(n^{\frac{3}{2}})$, but I don't see how this can help me here, can it?
Any hints, are appreciated.
Thanks.