#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  vector<pair<string, string> > lis(n);
  for (int i = 0; i < n; ++i) {
    cin >> lis[i].first >> lis[i].second;
  }
  int s = 0;
  for (int i = 0; i < n; ++i) {
    bool was = false;
    for (int j = 0; j < i; ++j) {
      if (lis[i] == lis[j]) {
        was = true;
      }
    }
    if (!was) {
      ++s;
    }
  }
  cout << s;
  return 0;
}
