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: Runtime Error)

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

class Progaram
{
    static void Main(string[] args)
    {
        var n = Int32.Parse(Console.ReadLine());
        var sl = new List<Int64>();
        for (var i = 0; n > i; i++)
        {
            var s = Console.ReadLine();
            var sc = s.ToCharArray();
            var nl = "";
            foreach (var j in sc)
            {
                nl += ((Int32)j - (Int32)'a' + 1).ToString();
            }
            sl.Add(Int32.Parse(nl));
        }
        sl = sl.OrderBy(x => x).ToList();
        for (var i = 0; sl.Count > i; i++)
        {
            var a = sl[i];
            var q = 1;
            while (true)
            {
                if (i + q == sl.Count) break;
                //Console.WriteLine(sl[i]);
                //Console.WriteLine(sl[i + q]);
                if (sl[i + q] == a) sl.RemoveAt(i + q);
                else break;
            }
        }
        Console.WriteLine(sl.Count);
    }
}