#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x, ans = 0;
  cin >> n;
  string name[n], color[n];
  for (int i = 0; i < n; i++) {
    cin >> name[i] >> color[i];
  }
  for (int i = 0; i < n; i++) {
    x = 0;
    for (int j = i + 1; j < n; j++) {
      if (name[i] == name[j] && color[i] == color[j]) x++;
    }
    if (x == 0) ans++;
  }
  cout << ans;
}
