/* You are given n pairs of strings. Two pairs (a,b) and (c,d) are identical if a=c and b=d. That also implies (a,b) is not same as (b,a). After taking each pair as input, you need to print number of unique pairs you currently have. Note: Brute force solution will not earn full points. */ import java.io.*; import java.util.*; import java.text.*; import java.math.*; import java.util.regex.*; public class Hashset { public static void main(String[] args) { /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */ Scanner s = new Scanner(System.in); int sum = s.nextInt(); s.nextLine(); HashSet hs = new HashSet(); for (int i=0;i