package main

import "fmt"

func main() {
	var n int
	fmt.Scan(&n)
	m := make(map[string]bool)
	ss := make([]string,n,n)
	for i:= range ss {
		var s string
		fmt.Scan(&s)
		ss[i]=s
		for _,t:=range ss[:i] {
			m[s+t]=true
			m[t+s]=true
		}
	}
	fmt.Println(len(m))
}