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

public class B
{
    InputReader2365 in;
    PrintWriter out;

    void run() throws IOException
    {
        in = new InputReader2365(System.in);
        out = new PrintWriter(new OutputStreamWriter(System.out));
        solve();
        out.flush();
    }

    public static void main(String[] args) throws IOException
    {
        new B().run();
    }
    void solve() throws IOException
    {
        int n = in.readInt();
        int ans[ ] =  new int[n];
        for (int i = 0; i < n; i++)
        {
            ans[i] = Long.bitCount(in.readLong());
        }
//        Arrays.sort(ans);
//        long x = 0;
//        for (int i = 0; i < ans.length; i++)
//        {
//            int cnt = 1;
//            int j;
//            for(j = i+1; j< ans.length && ans[j] == ans[i]; j++)
//            {
//                cnt++;
//            }
//            i = j-1;
//            x += func(cnt);
//        }
//        out.println(x);
        long x = 0;
        HashMap<Integer, Integer> set = new HashMap<Integer, Integer>();
        for (int i = 0; i < ans.length; i++)
        {
            Integer f = set.get(ans[i]);
            if(f == null)
            {
                set.put(ans[i], 1);
                continue;
            }
            else
            {
                x += f;
                set.put(ans[i], f+1);
            }
                
        }
        out.println(x);
    }

}


class InputReader2365
{
    private InputStream stream;
    private byte[] buf = new byte[1024];
    private int curChar;
    private int numChars;

    public InputReader2365(InputStream stream)
    {
        this.stream = stream;
    }

    public int read()
    {
        if (numChars == -1)
            throw new InputMismatchException();
        if (curChar >= numChars)
        {
            curChar = 0;
            try
            {
                numChars = stream.read(buf);
            }
            catch (IOException e)
            {
                throw new InputMismatchException();
            }
            if (numChars <= 0)
                return -1;
        }
        return buf[curChar++];
    }

    public int readInt()
    {
        int c = read();
        while (isSpaceChar(c))
            c = read();
        int sgn = 1;
        if (c == '-')
        {
            sgn = -1;
            c = read();
        }
        int res = 0;
        do
        {
            if (c < '0' || c > '9')
                throw new InputMismatchException();
            res *= 10;
            res += c - '0';
            c = read();
        } while (!isSpaceChar(c));
        return res * sgn;
    }

    public String readString()
    {
        int c = read();
        while (isSpaceChar(c))
            c = read();
        StringBuffer res = new StringBuffer();
        do
        {
            res.appendCodePoint(c);
            c = read();
        } while (!isSpaceChar(c));
        return res.toString();
    }

    public Long readLong()
    {
        return Long.parseLong(readString());
    }

    public Double readDouble()
    {
        return Double.parseDouble(readString());
    }

    public static boolean isSpaceChar(int c)
    {
        return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    }
}