#include <bits/stdc++.h>
using namespace std;
int n, ans;
string a[105], b[105];
int main() {
  cin >> n;
  for (int i = 1; i <= n; i++) {
    bool f = 1;
    cin >> a[i] >> b[i];
    for (int j = 1; j < i; j++)
      if (a[i] == a[j] && b[i] == b[j]) f = 0;
    if (f) ans++;
  }
  cout << ans;
  return 0;
}
