import java.util.*;
import java.io.*;
public class swapped{
    public static void main ( String [] args){
        Scanner in = new Scanner(System.in);
        int time = in.nextInt();
        HashMap<Integer,Long>a = new HashMap<Integer,Long>();
        for ( int i = 0;i<time;i++){
            int num = in.nextInt();
            if ( a.containsKey(num)){
                a.put(num, a.get(num)+1);
            }else{
                a.put(num, 1L);
            }
        }

        Long count = (long)time*(time-1)/2L;
        for(long number:a.values()){
            count-=number*(number-1)/2;
        }
        System.out.println(count);
    }
}