#include <bits/stdc++.h>
using namespace std;

int main() {
  int N, C = 0; cin >> N;
  vector<int> A(N); for (int &B : A) cin >> B;
  for (int i = 0; i < N; i++) {
    int B; cin >> B;
    if (B >= A.at(i)) C++;
  }
  cout << C << endl;
}