import sys

int1 = lambda x: int(x) - 1

# input = lambda: sys.stdin.buffer.readline()
input = lambda: sys.stdin.readline().rstrip()
ii = lambda: int(input())
i1 = lambda: int1(input())
mi = lambda: map(int, input().split())
mi1 = lambda: map(int1, input().split())
li = lambda: list(mi())
li1 = lambda: list(mi1())
lli = lambda n: [li() for _ in range(n)]

INF = float("inf")
# mod = int(1e9 + 7)
mod = 998244353

n = ii()
s = input()
t = input()

x = 0
y = 0
for i in range(n):
    x += s[i] != t[i]
    y += s[i] != t[-1 - i]

ans = INF
if ~x & 1:
    ans = min(ans, x)
if y & 1:
    ans = min(ans, y)
print(ans)