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