#include <bits/stdc++.h>
using namespace std;
struct xx {
  char name[20], color[20];
} x[101];
int cmp(const void *x, const void *y) {
  struct xx x1 = *(struct xx *)x;
  struct xx y1 = *(struct xx *)y;
  if (strcmp(x1.name, y1.name))
    return (strcmp(x1.name, y1.name));
  else
    return (strcmp(x1.color, y1.color));
}
int main() {
  int n;
  while (~scanf("%d", &n)) {
    int ant = 0;
    for (int i = 0; i < n; i++) {
      scanf("%s %s", x[i].name, x[i].color);
    }
    qsort(x, n, sizeof(x[0]), cmp);
    for (int i = 0; i < n - 1; i++) {
      if (!strcmp(x[i].name, x[i + 1].name) &&
          !strcmp(x[i].color, x[i + 1].color)) {
        ant++;
      }
    }
    printf("%d\n", n - ant);
  }
  return 0;
}
