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# (.NET Core 3.1.201) (judge verdict: Time Limit Exceeded)

using System;
using System.Collections.Generic;
class Program
{
    static void Main()
    {
        int n = int.Parse(Console.ReadLine());
        List<string> L = new List<string>();
        for(int i=0; i<n; i++)
        {
            string s = Console.ReadLine();
            if (i >= 1)
            {
                for(int j=0; j < L.Count; j++)
                {
                    if (L[j] == s) goto again;
                }
            }
            L.Add(s);
            again:;
        }
        Console.WriteLine(L.Count);
    }
}