import java.util.*;

class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		long co = 0;
		HashMap<String, Long> l = new HashMap<String, Long>();
		for (int i = 0; i < N; i++) {
			char[] c = sc.next().toCharArray();
			Arrays.sort(c);
			String S = new String(c);
			if (l.containsKey(S)) {
				l.put(S, l.get(S) + 1);
				co += l.get(S);
			} else {
				l.put(S, (long) 0);
			}
		}
		sc.close();
		System.out.println(co);
	}

}
/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