import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        Long output = new Long("0");
        Hashtable<String,Long> ht = new Hashtable<String,Long>();
		// 整数の入力
		int N = sc.nextInt();
		for(int i = 1; i <= N; i++){
          char[] tmp = sc.next().toCharArray();
          Arrays.sort(tmp);
          String tmp2 = new String(tmp);
          if(ht.get(tmp2) == null){
            ht.put(tmp2,new Long("1"));
          }else{
            output += ht.get(tmp2);
            ht.put(tmp2,ht.get(tmp2) + 1);
          }
        }
		System.out.println(output);
		
		// 出力
		
	}
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz