Dima got into number sequences. Now he's got sequence a1, a2, ..., an, consisting of n positive integers. Also, Dima has got a function f(x), which can be defined with the following recurrence:

  * f(0) = 0; 
  * f(2·x) = f(x); 
  * f(2·x + 1) = f(x) + 1. 



Dima wonders, how many pairs of indexes (i, j) (1 ≤ i < j ≤ n) are there, such that f(ai) = f(aj). Help him, count the number of such pairs. 

Input

The first line contains integer n (1 ≤ n ≤ 105). The second line contains n positive integers a1, a2, ..., an (1 ≤ ai ≤ 109).

The numbers in the lines are separated by single spaces.

Output

In a single line print the answer to the problem.

Please, don't use the %lld specifier to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams or the %I64d specifier.

Examples

Input

3
1 2 4


Output

3


Input

3
5 3 1


Output

1

Note

In the first sample any pair (i, j) will do, so the answer is 3.

In the second sample only pair (1, 2) will do.
//package Round_167;

import java.util.*;
import java.io.*;

import static java.lang.Math.*;

public class b {

    int f(int n){
        if (n == 0) return 0;
        if (n % 2 == 0) return f(n / 2);
        else 
            return f(n / 2) + 1;
    }
    
    void solve() throws Exception {
        int n = in.nextInt();
        int [] a = in.readIntArray(n);
        HashMap<Integer, Integer> hash = new HashMap<Integer, Integer>();
        long count = 0;
        long [] u = new long[n];
        for (int i = 0; i<n; i++){
            int t = f(a[i]);
            if (hash.containsKey(t)){
                u[hash.get(t)]++;
            }else 
                hash.put(t, i);
        }
        for (long x : u)
            count += ((x  + 1) * x) / 2;
        out.println(count);
    }

    FastScanner in;
    PrintWriter out;

    String input = "";
    String output = "";

    void run() {
        try {
            if (input.length() > 0) {
                in = new FastScanner(new BufferedReader(new FileReader(input)));
            } else
                in = new FastScanner(new BufferedReader(new InputStreamReader(
                        System.in)));
            if (output.length() > 0)
                out = new PrintWriter(new FileWriter(output));
            else
                out = new PrintWriter(System.out);

            solve();

            out.flush();
            out.close();
        } catch (Exception ex) {
            ex.printStackTrace();
            out.flush();
            out.close();
        } finally {
            out.close();
        }
    }

    public static void main(String[] args) {
        new b().run();
    }

    class FastScanner {
        BufferedReader bf;
        StringTokenizer st;

        public FastScanner(BufferedReader bf) {
            this.bf = bf;
        }

        public String next() throws IOException {
            while (st == null || !st.hasMoreTokens())
                st = new StringTokenizer(bf.readLine());
            return st.nextToken();
        }

        public int nextInt() throws IOException {
            return Integer.parseInt(next());
        }

        public String nextLine() throws IOException {
            return bf.readLine();
        }

        public long nextLong() throws IOException {
            return Long.parseLong(next());
        }

        public double nextDouble() throws IOException {
            return Double.parseDouble(next());
        }

        public int[] readIntArray(int n) throws IOException {
            int[] array = new int[n];
            for (int i = 0; i < n; i++)
                array[i] = this.nextInt();
            return array;
        }

        public long[] readLongArray(int n) throws IOException {
            long[] array = new long[n];
            for (int i = 0; i < n; i++)
                array[i] = this.nextLong();
            return array;
        }

    }

}
