#include <bits/stdc++.h>
using namespace std;
long long i, n, t, q, j;
map<string, string> m;
string a[1000], b[1000], y;
int main() {
  cin >> n;
  for (i = 1; i <= n; i++) cin >> a[i] >> b[i];
  for (i = 1; i <= n; i++) {
    q = 1;
    for (j = 1; j < i; j++)
      if (a[j] == a[i] && b[j] == b[i]) q = 0;
    t = t + q;
  }
  cout << t;
}
