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 JavaScript (Node.js 12.16.1) (judge verdict: Time Limit Exceeded)

function main(arg) {
  var N = parseInt(arg[0])
  var gacha = arg.slice(1)
  // 重複を削除したリスト
  var b = gacha.filter(function (x, i, self) {
            return self.indexOf(x) === i;
        });
  console.log(b.length)
}

main(require("fs").readFileSync("/dev/stdin", "utf8").trim().split('\n'));