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