#include <bits/stdc++.h>
using namespace std;
int a[1010], b[1010], n;
int get_min(int* x) {
  int mn = 100000, cand = 0;
  for(int i = 0; i < n; i++) {
    if(x[i] == 0) continue;
    if(x[i] < mn) {
      mn = x[i];
      cand = i;
    }
  }
  return cand;
}
int get_min_gt(int* x, int tar) {
  int mn = 10000000, cand = -1;
  for(int i = 0; i < n; i++) {
    if(x[i] == 0 || x[i] < tar) continue;
    if(x[i] < mn) {
      mn = x[i];
      cand = i;
    }
  }
  return cand;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cin >> n;
  for(int i = 0; i < n; i++) {
    cin >> a[i];
  }
  for(int i = 0; i < n; i++) {
    cin >> b[i];
  }
  int ans = 0;
  for(int i = 0; i < n; i++) {
    int x = get_min(a), y = get_min_gt(b, a[x]);
    if(y == -1) {
      for(int i = 0; i < n; i++) if(a[i]) ans++;
      cout << ans << endl;
      exit(0);
    }
    else {
      a[x] = b[y] = 0;
    }

    x = get_min(b);
    y = get_min_gt(a, b[x]);
    if(y == -1) {
      cout << ans << endl;
      exit(0);
    }
    else {
      a[y] = b[x] = 0;
      ans++;

    }
  }
  return 0;
}