#include <bits/stdc++.h>
using namespace std;
struct leave {
  char a[12];
  char b[12];
} lea[102];
int n, i, j;
int main() {
  cin >> n;
  cin >> lea[0].a >> lea[0].b;
  for (i = 1; i < n; i++) {
    cin >> lea[i].a >> lea[i].b;
    for (j = 0; j < i; j++) {
      if (strcmp(lea[i].a, lea[j].a) == 0 && strcmp(lea[i].b, lea[j].b) == 0) {
        n--;
        i--;
        break;
      }
    }
  }
  cout << n;
  return 0;
}
