#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int N, M, i, j, k, a, b, c, d, x, y, z, m, n, s, t;
  string A, B, C, D, E;
  vector<string> P;
  cin >> N;
  for (i = 1; i <= N; i++) {
    cin >> A >> B;
    D = '*';
    C = A + D;
    E = C + B;
    P.push_back(E);
  }
  for (i = 0; i < N; i++) {
    if (P[i] != "???") {
      for (j = i + 1; j < N; j++) {
        if (P[i] == P[j]) {
          P[j] = "???";
        }
      }
    }
  }
  m = 0;
  for (i = 0; i < N; i++) {
    if (P[i] != "???") {
      m++;
    }
  }
  cout << m << endl;
  return 0;
}
