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

ans = 10 ** 9
cnt = 0
for a, b in zip(s, t):
    cnt += (a != b)
if(cnt % 2 == 0):
  ans = cnt
cnt = 0
for a, b in zip(s[::-1], t):
    cnt += (a != b)
if(cnt % 2 == 1):
  ans = min(ans, cnt)
if(ans == 10 ** 9):
  exit(1)
print(ans)