s = input()
red = s.count("0")
blue = s.count("1")
print(min(red, blue)*2) s = input() s input() input red = s.count("0") red s.count("0") s.count s count "0" blue = s.count("1") blue s.count("1") s.count s count "1" print(min(red, blue)*2) print min(red, blue)*2 min(red, blue) min red blue 2 red = s.count("0") s.count("0") red blue = s.count("1") s.count("1") blue s = input() input() s
s = input()
red = s.count("0")
blue = s.count("1")
print(min(red, blue)*2)