s = str(input())
x = s.count('0')
y = s.count('1')
print(min(x,y)*2) s = str(input()) s str(input()) str input() input x = s.count('0') x s.count('0') s.count s count '0' y = s.count('1') y s.count('1') s.count s count '1' print(min(x,y)*2) print min(x,y)*2 min(x,y) min x y 2 s = str(input()) str(input()) s x = s.count('0') s.count('0') x y = s.count('1') s.count('1') y
s = str(input())
x = s.count('0')
y = s.count('1')
print(min(x,y)*2)