#include <bits/stdc++.h>
char a[100][2][11];
int main() {
  int n, i;
  scanf("%d", &n);
  int c = 0;
  char s1[11], s2[11];
  bool has = false;
  for (int i = 0; i < n; i++) {
    scanf("%s %s", s1, s2);
    has = false;
    for (int j = 0; j < c; j++) {
      if (!strcmp(s1, a[j][0]) && !strcmp(s2, a[j][1])) {
        has = true;
        break;
      }
    }
    if (!has) {
      strcpy(a[c][0], s1);
      strcpy(a[c++][1], s2);
    }
  }
  printf("%d\n", c);
  return 0;
}
