from collections import Counter
s = Counter(input())
print(2*min(s['0'],s['1'])) from collections import Counter s = Counter(input()) s Counter(input()) Counter input() input print(2*min(s['0'],s['1'])) print 2*min(s['0'],s['1']) 2 min(s['0'],s['1']) min s['0'] s '0' s['1'] s '1' s = Counter(input()) Counter(input()) s
from collections import Counter
s = Counter(input())
print(2*min(s['0'],s['1']))