#include <iostream>

using namespace std;

int main() {
    int n;
    int a[n];
    cin >> n;
    int cnt1 = 0, cnt2 = 0, cnt3 = 0, cnt4 = 0, cnt = 0;
    for(int i = 0; i < n; i++){
      cin >> a[i];
      if(a[i] == 1){
        cnt1++;
        cnt++;
      }
      else if(a[i] == 2){
        cnt2++;
        cnt++;
      }
      else if(a[i] == 3){
        cnt3++;
        cnt++;
      }
      else{
        cnt4++;
      }
    }
    int sum = cnt4;
    if(cnt3 > cnt1){
      sum += (cnt3-cnt1);
    }
    else if(cnt3 == cnt1){
      sum += cnt3;
    }
    else if(cnt3 < cnt1){
      cnt += (cnt1-cnt3);
    }
    cout << cnt4 + ;
}