#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m = 0;
  cin >> n;
  string a[n], b[n];
  for (int i = 0; i < n; i++) {
    cin >> a[i] >> b[i];
    bool t = true;
    for (int j = 0; j < i; j++) {
      if (a[i] == a[j] && b[i] == b[j]) t = false;
    }
    if (t == true) m++;
  }
  cout << m;
  return 0;
}
