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: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace C
{
    class Program
    {
        static void Main(string[] args)
        {
            string n = Console.ReadLine();
            int N = int.Parse(n);

            var dict = new Dictionary<string, int>();
            var list = new List<string>();

            for (int i = 0; i < N; i++)
            {
                string S = Console.ReadLine();
                if (dict.ContainsKey(S) == false)
                {
                    dict.Add(S, i);
                    //dict.Sort();
                }
                //if(list.BinarySearch(S) < 0)
                //{
                //    list.Add(S);
                //    list.Sort();
                //}
            }

            Console.WriteLine(dict.Count);

        }
    }
}