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: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;

namespace AtCoderCs
{

    class Program
    {

        const int Mod = 1000000007;

        static void Main()
        {

            var num = int.Parse(Console.ReadLine());
            var list = Enumerable.Repeat(new List<string>(), 'z' - 'a' + 1).ToArray();

            for (int i = 0; i < num; i++)
            {

                var str = Console.ReadLine();
                if (!list[str[0] - 'a'].Any(x => x == str)) list[str[0] - 'a'].Add(str);

            }

            Console.WriteLine(list.Sum(x => x.Count));

        }


    }
}