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: Time Limit Exceeded)

using System;

class Program
{
  static int ans = 0;
  static string tmp;
  static void Main()
  {
    int n = int.Parse(Console.ReadLine());
    string[] s = new string[n];
    for(int i = 0; i < n; i++)
    {
      tmp = Console.ReadLine();
      if (Array.IndexOf(s, tmp) == -1)
      {
        s[i] = tmp;
        ans++;
      }
    }
    Console.WriteLine(ans);
  }
}