import java.util.Arrays;
import java.util.HashMap;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int N = scanner.nextInt();

        scanner.nextLine();

        long ans = 0;
        HashMap<String, Integer> map = new HashMap<>();
        for(int i = 0; i < N; i++) {
            String line = scanner.nextLine();
            char[] c = line.toCharArray();
            Arrays.sort(c);
            String sortedLine = new String(c);

            if(map.containsKey(sortedLine)) {
                ans += map.get(sortedLine);
                map.put(sortedLine, map.get(sortedLine) + 1);
            } else {
                map.put(sortedLine, 1);
            }
        }

        System.out.println(ans);

        scanner.close();
    }
}
/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