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

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		String count = sc.next();
		long ans = 0;
		Map<String, Long> map = new HashMap<String, Long>();

		for (int i = 0; i < Integer.parseInt(count); i++) {
			char[] ary = sc.next().toCharArray();
			Arrays.sort(ary);
			String c = 	new String(ary);
				if (map.containsKey(c)) {
					ans = ans + map.get(c);
					map.put(c, map.get(c) + 1);
				} else {
					map.put(c, (long) 1);
				}
			}

		System.out.println(ans);
	}

}
/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