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 Java (OpenJDK 11.0.6) (judge verdict: Wrong Answer)

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Long n,count = (long)0;
        List<String> s = new ArrayList<String>();
        List<String> s1 = new ArrayList<String>();
        Scanner sc = new Scanner(System.in);
        n = sc.nextLong();
        for(int i = 0; i < n; i++){
            s.add(sc.next());
            for(int j = 1; j < s.size(); j++){
                if(s.get(i).equals(s.get(j))){
                    if(s1.size() == 0){
                        count++;
                        s1.add(s.get(i));
                    }
                }
            }
        }
        for(int i = 1; i < s1.size(); i++){
            if(s1.get(i-1).equals(s1.get(i))){
                count --;
            }
        }
        System.out.println(count);
    }
}