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"
)

const (
	initialBufSize = 10000
	maxBufSize     = 100000000
)

var sc *bufio.Scanner = func() *bufio.Scanner {
	sc := bufio.NewScanner(os.Stdin)
	buf := make([]byte, initialBufSize)
	sc.Buffer(buf, maxBufSize)
	return sc
}()

// Input number
func scanIntNum() (num int) {
	sc.Scan()

	num, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return num
}

// Input string
func scanString() (s string) {
	sc.Scan()
	return sc.Text()
}

func main() {
	N := scanIntNum()
	types := make(map[string]int)

	var S string
	for i := 0; i < N; i++ {
		S = scanString()
		types[S]++
	}
	fmt.Println(len(types))
}