#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using vll = vector<long long>;
using vvll = vector<vector<long long>>;
using vs = vector<string>;
#define lln \
  ll n;     \
  cin >> n;
#define REP(i, n) for (long long i = 0; i < n; i++)
#define REP2(i, s, e) for (long long i = s; i < e; i++)
#define UNIQUE_VECTOR(v) v.erase(unique(v.begin(), v.end()))
ll gcd(ll x, ll y) { return (x % y) ? gcd(y, x % y) : y; }
ll lcm(ll x, ll y) { return x / gcd(x, y) * y; }

int main() {
  lln;
  string s, t;
  cin >> s >> t;
  ll cnt = 0;
  REP(i, n) {
    if (s[i] == '1') {
      cnt++;
    }
    if (t[i] == '1') {
      cnt--;
    }
  }
  if (cnt % 2) {
    reverse(t.begin(), t.end());
  } else {
  }
  ll ans = 0;
  REP(i, n) {
    if (s[i] != t[i]) {
      ans++;
    }
  }
  cout << ans << endl;
}

/*
0110111010
1001010011
@@@@@.@..@

0110111010
1100101001
@.@..@..@@
*/