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(void)
{
	int N;
	cin >> N;

	vector<string> S(N);
	for (int i = 0; i < N; i++) {
		cin >> S.at(i);
	}

	int cnt = 0;
	for (int i = 0; i < N; i++) {
		int flag = 0;
		for (int j = 0; j < i; j++) {
			if (i != j && S.at(i).at(0) == S.at(j).at(0)) {
				if (S.at(i) == S.at(j)){
					flag++;
					break;
				}
			}
		}
		if (flag == 0 || i == 0) cnt++;
		flag = 0;
	}

	cout << cnt << endl;
	return 0;
}