s = input()

c0 = s.count("0")
c1 = s.count("1")
print(2 * min(c0, c1)) s = input() s input() input c0 = s.count("0") c0 s.count("0") s.count s count "0" c1 = s.count("1") c1 s.count("1") s.count s count "1" print(2 * min(c0, c1)) print 2 * min(c0, c1) 2 min(c0, c1) min c0 c1 s = input() input() s c1 = s.count("1") s.count("1") c1 c0 = s.count("0") s.count("0") c0
s = input()

c0 = s.count("0")
c1 = s.count("1")
print(2 * min(c0, c1))