#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, arr[601] = {0}, a;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a;
    if (a > 0) arr[a]++;
  }
  int Ans = 0;
  for (int j = 0; j < 601; j++) {
    if (arr[j] > 0) Ans++;
  }
  cout << Ans;
  return 0;
  ;
}
