N = int(input())
S = input()
T = input()
if S == T:
    print(0)
    exit()

RS = S[::-1]
cnt0 = 0
cnt1 = 0
for i in range(N):
    if S[i] != T[i]:
        cnt0 += 1
    if RS[i] != T[i]:
        cnt1 += 1
ans = 10 ** 6 + 1
if cnt0 % 2 == 0:
    ans = cnt0
else:
    ans = cnt1

print(ans)