#include <stdio.h>

int main () {
  int n = 0;
  char s[1000001] = "";
  char t[1000001] = "";
  
  int res = 0;
  
  int ans = 0;
  int tmp = 0;
  
  res = scanf("%d", &n);
  res = scanf("%s", s);
  res = scanf("%s", t);
  
  for (int i = 0; i < n; i++) {
    if (s[i] != t[i]) {
      ans++;
    }
    if (s[i] != t[n-i-1]) {
      tmp++;
    }
  }
  
  if (ans%2 == 1) {
    ans = tmp;
  }
  
  printf("%d\n", ans);
  return 0;
}