S = input()

num_0 = S.count('0')
num_1 = S.count('1')

print(min(num_0, num_1)*2) S = input() S input() input num_0 = S.count('0') num_0 S.count('0') S.count S count '0' num_1 = S.count('1') num_1 S.count('1') S.count S count '1' print(min(num_0, num_1)*2) print min(num_0, num_1)*2 min(num_0, num_1) min num_0 num_1 2 S = input() input() S num_1 = S.count('1') S.count('1') num_1 num_0 = S.count('0') S.count('0') num_0
S = input()

num_0 = S.count('0')
num_1 = S.count('1')

print(min(num_0, num_1)*2)