After learning a lot about space exploration, a little girl named Ana wants to change the subject.

Ana is a girl who loves palindromes (string that can be read the same backwards as forward). She has learned how to check for a given string whether it's a palindrome or not, but soon she grew tired of this problem, so she came up with a more interesting one and she needs your help to solve it:

You are given an array of strings which consist of only small letters of the alphabet. Your task is to find how many palindrome pairs are there in the array. A palindrome pair is a pair of strings such that the following condition holds: at least one permutation of the concatenation of the two strings is a palindrome. In other words, if you have two strings, let's say "aab" and "abcac", and you concatenate them into "aababcac", we have to check if there exists a permutation of this new string such that it is a palindrome (in this case there exists the permutation "aabccbaa"). 

Two pairs are considered different if the strings are located on different indices. The pair of strings with indices (i,j) is considered the same as the pair (j,i).

Input

The first line contains a positive integer N (1 ≤ N ≤ 100 000), representing the length of the input array.

Eacg of the next N lines contains a string (consisting of lowercase English letters from 'a' to 'z') — an element of the input array. 

The total number of characters in the input array will be less than 1 000 000.

Output

Output one number, representing how many palindrome pairs there are in the array.

Examples

Input

3
aa
bb
cd


Output

1


Input

6
aab
abcac
dffe
ed
aa
aade


Output

6

Note

The first example:

  1. aa + bb → abba. 



The second example:

  1. aab + abcac = aababcac → aabccbaa
  2. aab + aa = aabaa
  3. abcac + aa = abcacaa → aacbcaa
  4. dffe + ed = dffeed → fdeedf
  5. dffe + aade = dffeaade → adfaafde
  6. ed + aade = edaade → aeddea
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.HashMap;
import java.io.IOException;
import java.util.InputMismatchException;
import java.io.InputStreamReader;
import java.io.BufferedOutputStream;
import java.util.StringTokenizer;
import java.io.Closeable;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.Flushable;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
	static class TaskAdapter implements Runnable {
		@Override
		public void run() {
			InputStream inputStream = System.in;
			OutputStream outputStream = System.out;
			Input in = new Input(inputStream);
			Output out = new Output(outputStream);
			IPalindromePairs solver = new IPalindromePairs();
			solver.solve(1, in, out);
			out.close();
		}
	}

	public static void main(String[] args) throws Exception {
		Thread thread = new Thread(null, new TaskAdapter(), "", 1<<29);
		thread.start();
		thread.join();
	}
	static class IPalindromePairs {
		public IPalindromePairs() {
		}

		public void solve(int kase, Input in, Output pw) {
			int n = in.nextInt();
			String[] arr = new String[n];
			int[] mask = new int[n];
			for(int i = 0; i<n; i++) {
				arr[i] = in.next();
				for(int j = 0; j<arr[i].length(); j++) {
					mask[i] ^= 1<<arr[i].charAt(j)-'a';
				}
			}
			HashMap<Integer, Integer> hm = new HashMap<>();
			long ans = 0;
			for(int i = 0; i<n; i++) {
				ans += hm.getOrDefault(mask[i], 0);
				for(int j = 0; j<26; j++) {
					ans += hm.getOrDefault(mask[i]^(1<<j), 0);
				}
				hm.put(mask[i], hm.getOrDefault(mask[i], 0)+1);
			}
			pw.println(ans);
		}

	}

	static class Input {
		BufferedReader br;
		StringTokenizer st;

		public Input(InputStream is) {
			this(is, 1<<20);
		}

		public Input(InputStream is, int bs) {
			br = new BufferedReader(new InputStreamReader(is), bs);
			st = null;
		}

		public boolean hasNext() {
			try {
				while(st==null||!st.hasMoreTokens()) {
					String s = br.readLine();
					if(s==null) {
						return false;
					}
					st = new StringTokenizer(s);
				}
				return true;
			}catch(Exception e) {
				return false;
			}
		}

		public String next() {
			if(!hasNext()) {
				throw new InputMismatchException();
			}
			return st.nextToken();
		}

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

	}

	static class Output implements Closeable, Flushable {
		public StringBuilder sb;
		public OutputStream os;
		public int BUFFER_SIZE;
		public boolean autoFlush;
		public String LineSeparator;

		public Output(OutputStream os) {
			this(os, 1<<16);
		}

		public Output(OutputStream os, int bs) {
			BUFFER_SIZE = bs;
			sb = new StringBuilder(BUFFER_SIZE);
			this.os = new BufferedOutputStream(os, 1<<17);
			autoFlush = false;
			LineSeparator = System.lineSeparator();
		}

		public void println(long l) {
			println(String.valueOf(l));
		}

		public void println(String s) {
			sb.append(s);
			println();
			if(autoFlush) {
				flush();
			}else if(sb.length()>BUFFER_SIZE >> 1) {
				flushToBuffer();
			}
		}

		public void println() {
			sb.append(LineSeparator);
		}

		private void flushToBuffer() {
			try {
				os.write(sb.toString().getBytes());
			}catch(IOException e) {
				e.printStackTrace();
			}
			sb = new StringBuilder(BUFFER_SIZE);
		}

		public void flush() {
			try {
				flushToBuffer();
				os.flush();
			}catch(IOException e) {
				e.printStackTrace();
			}
		}

		public void close() {
			flush();
			try {
				os.close();
			}catch(IOException e) {
				e.printStackTrace();
			}
		}

	}
}


