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 in = new Scanner(System.in);
		int n = in.nextInt();
		Map<String, Long> map = new HashMap<>();
		long total = 0;
		for ( int i = 0; i < n; i++ ) {
			char[] s = in.next().toCharArray();
			Arrays.sort(s);
			String key = new String(s);
			Long cnt = (map.containsKey(key) ? map.get(key) + 1 : 1);
			map.put(key, cnt);
			total += cnt - 1;
		}

		System.out.println(total);
		in.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