n = int(input())
s = input()
t = input()

cnt = 0
for a, b in zip(s, t):
    cnt += (a != b)
ans = cnt + 2 * (cnt & 1)
cnt = 0
for a, b in zip(s[::-1], t):
    cnt += (a != b)
ans = min(ans, cnt + 2 - 2 * (cnt & 1))
print(ans)