package main

import (
	"fmt"
)

func main() {
	var n int
	fmt.Scan(&n)
	m := make(map[string]int, n)
	re := make(map[string]struct{}, n)
	var word string
	for i := 0; i < n; i++ {
        fmt.Scan(&word)
		m[word]++
        if _,ok:=re[word];!ok && m[word] > len(re){
            re[word] = struct{}{}
        }
	}
	fmt.Print(len(re))
}