S=input()
one=S.count("1")
zero=S.count("0")
ans=min(one,zero)*2
print(ans) S=input() S input() input one=S.count("1") one S.count("1") S.count S count "1" zero=S.count("0") zero S.count("0") S.count S count "0" ans=min(one,zero)*2 ans min(one,zero)*2 min(one,zero) min one zero 2 print(ans) print ans ans=min(one,zero)*2 min(one,zero)*2 ans zero=S.count("0") S.count("0") zero S=input() input() S one=S.count("1") S.count("1") one
S=input()
one=S.count("1")
zero=S.count("0")
ans=min(one,zero)*2
print(ans)
