import sys
def input():
  return sys.stdin.readline()[:-1]
N=int(input())
S=input()
T=input()
ans=10**10
tmp=sum([1 if S[i]!=T[i] else 0 for i in range(N)])
if tmp%2==0: ans=min(ans,tmp)
tmp=sum([1 if S[-i-1]!=T[i] else 0 for i in range(N)])
if tmp%2==1: ans=min(ans,tmp)
print(ans)