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;

namespace cswork {
    class Program {
        static void Main (string[] args) {
                        long n = Read();
            HashSet<string> set = new HashSet<string>();

            for(int i=0; i<n; i++){
                set.Add(ReadStr());
            }

            Write(set.Count);
            
            Exit ();
        }

        public static void Write (string str) {
            Console.WriteLine (str);
        }

        public static void Write (int i) {
            Console.WriteLine (i);
        }

        public static void Write (double d) {
            Console.WriteLine (d);
        }

        public static string ReadStr () {
            return Console.ReadLine ();
        }

        public static int ReadInt () {
            return int.Parse (Console.ReadLine ());
        }

        public static long Read () {
            return long.Parse (Console.ReadLine ());
        }

        public static double ReadDouble () {
            return double.Parse (Console.ReadLine ());
        }

        public static void Exit () { }

        public static List<string> ReadListStr () {
            return new List<string> (ReadStr ().Split (" "));
        }

        public static List<long> ReadList () {
            return ReadListStr ().ConvertAll (x => long.Parse (x));
        }
    }
}