S = input()
A = S.count("0")
B = S.count("1")
print(2*min(A, B)) S = input() S input() input A = S.count("0") A S.count("0") S.count S count "0" B = S.count("1") B S.count("1") S.count S count "1" print(2*min(A, B)) print 2*min(A, B) 2 min(A, B) min A B S = input() input() S A = S.count("0") S.count("0") A B = S.count("1") S.count("1") B
S = input()
A = S.count("0")
B = S.count("1")
print(2*min(A, B))