Problem:
Score : 300 points

Problem Statement

You drew lottery N times. In the i-th draw, you got an item of the kind represented by a string S_i.

How many kinds of items did you get?

Constraints

1 \leq N \leq 2\times 10^5

S_i consists of lowercase English letters and has a length between 1 and 10 (inclusive).

Input

Input is given from Standard Input in the following format:

N
S_1
:
S_N

Output

Print the number of kinds of items you got.

Sample Input 1

3
apple
orange
apple

Sample Output 1

2

You got two kinds of items: apple and orange.

Sample Input 2

5
grape
grape
grape
grape
grape

Sample Output 2

1

Sample Input 3

4
aaaa
a
aaa
aa

Sample Output 3

4

Solution in C++ (GCC 9.2.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;

int main() {
  int N;
  cin >> N;
  vector<string> vec(N);
  string S;
  for (int i = 0; i < N; i++) {
    cin >> S;
    vec.at(i) = S;
  }
  int counter = 0;
  for (int i = 0; i < N; i++) {
    for (int j = 0; j <= i; j++) {
      if (vec.at(i) == vec.at(j)) {
        counter++;
        break;
      }
    }
  }
  cout << counter << endl;
}