#include <bits/stdc++.h>
using namespace std;
const int MAX = 100000 + 5;
vector<string> a;
vector<string> b;
bool res;
int main() {
  string x, y;
  int n;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    res = true;
    cin >> x >> y;
    for (int j = 0; j < a.size(); j++) {
      if (x == a[j] && y == b[j]) {
        res = false;
        break;
      }
    }
    if (res) {
      a.push_back(x);
      b.push_back(y);
    }
  }
  cout << a.size() << endl;
}
