#include <bits/stdc++.h>
using namespace std;
int n;
string a[200], b[200];
int main() {
  cin >> n;
  for (int i = 0; i < n; ++i) cin >> a[i] >> b[i];
  int kol = 0;
  for (int i = 0; i < n; ++i)
    if (a[i] != "11") {
      ++kol;
      for (int j = i + 1; j < n; ++j)
        if (a[i] == a[j] && b[i] == b[j]) {
          a[j] = "11", b[j] = "11";
        }
    }
  cout << kol;
  return 0;
}
