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

class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int N = Integer.parseInt(sc.next());
    Map<String, Integer> map = new HashMap<>();
    
    char[] chars = new char[10];
    StringBuilder sb;
    long sum = 0;
    for (int i = 0; i < N; i++) {
      sc.next().getChars(0, 10, chars, 0);
      Arrays.sort(chars);
      sb = new StringBuilder();
      for (int j = 0; j < 10; j++) {
        sb.append(chars[j]);
      }
      
      String key = sb.toString();
      Integer val = map.get(key);
      if (val == null) {
        val = 1;
      } else {
        val++;
      }
      map.put(key, val);
      sum += val - 1;
    }
    
    System.out.println(sum);
  }
}
/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