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: Time Limit Exceeded)

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

int main()
{
    int N;
    cin >> N;
    vector<string> S(N);
    for (int i = 0; i<N; i++)
    {
        cin >> S.at(i);
    }
    int count = N;
    for (int i = 0; i < N; i++)
    {
        for (int j = i + 1; j < N; j++)
        {
            if (i != j && S.at(i) == S.at(j))
            {
                count--;
                S.at(i) = "aaaaaaaaaaaaaahkrstomnjaibgdfnabdi";
            }
        }
    }
    cout << count << endl;
}