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 Go (1.14.1) (judge verdict: Accepted)

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

var dict = make(map[string]string)

func addCollection(a string) {
	if _, ok := dict[a]; ok {
	} else {
		dict[a] = ""
	}
}

func main() {
	var scanner = bufio.NewScanner(os.Stdin)
	var p string
	if scanner.Scan() {
		p = scanner.Text()
	}
	N, _ := strconv.Atoi(p)
	for i := 0; i < N; i++ {
		if scanner.Scan() {
			addCollection(scanner.Text())
		}
	}
	fmt.Println(len(dict))
}