N = int(input())
S = list(input())
SR = S[::-1]
T = list(input())
scnt = sum([1 for s,t in zip(S,T) if s!=t])
srcnt = sum([1 for sr,t in zip(SR,T) if sr!=t])
if scnt%2==0 and srcnt%2==0:
    print(scnt)
elif scnt%2==0:
    print(min(scnt,srcnt))
elif srcnt%2==0:
    print(N)
else:
    print(srcnt)