from collections import * from itertools import * from functools import * from heapq import * import sys,math input = sys.stdin.readline N = int(input()) S = list(input())[:-1] T = list(input())[:-1] X = sum(S[i]!=T[i] for i in range(N)) if X%2: X += 2 Y = sum(S[N-1-i]!=T[i] for i in range(N)) if Y%2==0: Y += 1 print(min(X,Y))