#include <bits/stdc++.h>
using namespace std;
struct leaf {
  string name;
  string color;
};
bool exist(leaf l, vector<leaf> vleaf) {
  for (int i = 0; i < vleaf.size(); i++)
    if (vleaf[i].color == l.color && vleaf[i].name == l.name) return true;
  return false;
}
int main() {
  vector<leaf> vleaf;
  int n;
  cin >> n;
  leaf temp;
  for (int i = 0; i < n; i++) {
    cin >> temp.name >> temp.color;
    if (!exist(temp, vleaf)) vleaf.push_back(temp);
  }
  cout << vleaf.size();
  return 0;
}
