#include using namespace std; #define rep(i,n) for(int i=0;i<(n);++i) #define loop for(;;) #define trace(var) cerr<<">>> "<<#var<<" = "< inline ostream& operator<<(ostream&os, pair p) { return os << '(' << p.first << ", " << p.second << ')'; } template inline ostream& operator<<(ostream&os, tuple t) { return os << '(' << get<0>(t) << ", " << get<1>(t) << ", " << get<2>(t) << ')'; } template inline ostream& operator<<(ostream&os, vector v) { if (v.size() == 0) { return os << "(empty)"; } os << v[0]; for (int i=1, len=v.size(); i inline istream& operator>>(istream&is, vector&v) { rep (i, v.size()) is >> v[i]; return is; } // ^ > v < int dx[] = { -1, 0, 1, 0 }; int dy[] = { 0, 1, 0, -1 }; using vi = vector; using vvi = vector; using vd = vector; using vvd = vector; using vb = vector; const Integer M = 1000000000000000; vector> PascalTriangle(int n) { vector> cc(n); for (int i = 0; i < n; ++i) { cc[i].resize(i + 1); for (int j = 0; j <= i; ++j) { cc[i][j] = (!i || !j || i == j) ? 1 : cc[i-1][j] + cc[i-1][j-1]; if (cc[i][j] > M) cc[i][j] = M+1; } } return cc; } int main() { cin.tie(0); ios::sync_with_stdio(0); cout.setf(ios::fixed); cout.precision(10); random_device dev; mt19937 rand(dev()); int n; string s, t; cin >> n >> s >> t; int ans = 0; rep (i, n) { if (s[i] != t[i]) ++ans; } cout << ans << endl; return 0; }