N = gets.to_i
S = gets.chomp
T = gets.chomp

reversible_flip0 = 0 # 0 flip
reversible_flip1 = 0 # 1 flip
reversible_flip2 = 0 # 2 flip
irreversible_flip0 = 0 # 0 flip (non-reversed) or 2 flip (reversed)
irreversible_flip0_reverse = 0 # 2 flip (non-reversed) or 0 flip (reversed)
irreversible_flip1 = 0 # 1 flip

ans = 0

if S[N / 2] != T[N / 2]
    ans += 1
    N.times do |i|
        T[i] = T[i] == ?0 ? ?1 : ?0
    end
end

(N / 2).times do |i|
    j = N - 1 - i
    a, b, c, d = S[i], S[j], T[i], T[j]
    if c == d # reversible
        if a == c and b == d
            reversible_flip0 += 1
        elsif a != c and b != d
            reversible_flip2 += 1
        else
            reversible_flip1 += 1
        end
    else
        if a == c and b == d
            irreversible_flip0 += 1
        elsif a != c and b != d
            irreversible_flip0_reverse += 1
        else
            irreversible_flip1 += 1
        end
    end
end

flip = (reversible_flip1 + irreversible_flip1) % 2

if flip == 0
    ans += reversible_flip1 + 2 * reversible_flip2 + 2 * irreversible_flip0_reverse + irreversible_flip1
else
    ans += reversible_flip1 + 2 * reversible_flip2 + 2 * irreversible_flip0 + irreversible_flip1
end

puts ans