#include <bits/stdc++.h>
using namespace std;
class leaves {
 public:
  string tree;
  string color;
};
int indian_summer() {
  leaves *leaf;
  int n, a = 0;
  cin >> n;
  leaf = new (nothrow) leaves[n];
  for (int i = 0; i < n; i++) {
    cin >> leaf[i].tree >> leaf[i].color;
    a++;
    for (int j = 0; j < i; j++)
      if (leaf[j].tree == leaf[i].tree && leaf[j].color == leaf[i].color) {
        a--;
        break;
      }
  }
  cout << a;
  return 0;
}
int main() {
  int t;
  t = 1;
  for (int i = 0; i < t; i++) indian_summer();
  return 0;
}
