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.IO;
using System.Linq;
using System.Collections.Generic;
using System.Text;
using System.Numerics;

namespace abc164
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false });
            if (File.Exists("input.txt"))
            {
                Console.SetIn(new StreamReader("input.txt"));
            }
			solve_abc164C();
			Console.Out.Flush();

        }

        public static void solve_abc164C()
        {
            int n = Convert.ToInt32(Console.ReadLine());
            Dictionary<string, int> dic = new Dictionary<string, int>();
            int cnt = 0;
            for (int i = 0; i < n; i++)
            {
                string s = Console.ReadLine();
                if (!dic.ContainsKey(s))
                {
                    dic.Add(s, 0);
                    cnt++;
                }
            }
            Console.WriteLine(cnt);
        }

        public static void solve_abc164B()
        {
            int[] abcd = Array.ConvertAll(Console.ReadLine().Split(), int.Parse);
            int a = abcd[0];
            int b = abcd[1];
            int c = abcd[2];
            int d = abcd[3];
            if ((c + b - 1) / b <= (d + a - 1)/ d)
            {
                Console.WriteLine("Yes");
            }
            else
            {
                Console.WriteLine("No");
            }
        }

        public static void solve_abc164A()
        {
            int[] sw = Array.ConvertAll(Console.ReadLine().Split(), int.Parse);
            if (sw[1] >= sw[0])
            {
                Console.WriteLine("unsafe");
            }
            else
            {
                Console.WriteLine("safe");
            }
        }
    }
}