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 <iostream>
#include <string>
#include <vector>
using namespace std;

int main() {
	int n;
	vector<string> strVec;
	cin >> n;
	int count = n;
	for (int i = 0; i < n; i++) {
		string tmp = "";
		cin >> tmp;
		strVec.push_back(tmp);
	}
	for (int i = 0; i < n; i++) {
		for (int j = i + 1; j < n; j++) {
			if (i == n-1) {
				if (strVec.at(i) == "")count--;
				cout << count;
				return 0;
			}
			if (strVec.at(i) != "") {
				if (strVec.at(i) == strVec.at(j)) {
					count--;
					strVec.at(j) = "";
				}
			}
			else break;
		}
	}
	cout << count;

	return 0;

}