same as problem D

Nice Contest !
I spend lot's of time to solve problem G, but failed. Sharing another's way to solve problem Ex while using two map (or multiset). (link: https://atcoder.jp/contests/abc254/submissions/32236618)
Key point : Everytime to check both array's max element compared equal. If equal, then remove them, otherwise to make max_element divided by two.

It's really hard to understand.

Finally, i get ac while carefully handle answer not exist's case, but match is end. https://www.codechef.com/viewsolution/63881983

Problem "Minimum Hash" do not say solution not exist's answer is -1, which make me get lots of re or wa