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

import javax.swing.tree.TreeNode;
class Main{


	static final int MOD = 1000000007;

	static int MAX = 10000000;
	static	ArrayList<TreeNode> tree;
	static HashSet<Integer> set;
	static int[] ans;

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);			//文字の入力
		int n = sc.nextInt();
		
		HashMap<String,Integer> map = new HashMap<>();
		long ans = 0;

		for(int i = 0;i < n;i++){
			char[] cc = sc.next().toCharArray();
			Arrays.sort(cc);
			String s = new String(cc);
			int num = map.getOrDefault(s, 0);
			map.put(s, num+1);
			if(num >= 1){
				ans += num;
			}
		}
//		COMinit();  					//二項定理デーブル作成
		
//		for(int num:map.values()){
//			ans += COM(num, 2);
//
//		}
		System.out.println(ans);
		
		
		
	}

	static long fac[] = new long[MAX];
	static long finv[] = new long[MAX];
	static long inv[] = new long[MAX];

	

//テーブルの作成
	static void COMinit() {
		fac[0] = fac[1] = 1;
		finv[0] = finv[1] = 1;
		inv[1] = 1;
		for (int i = 2; i < MAX; i++){
			fac[i] = fac[i - 1] * i % MOD;
			inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;
			finv[i] = finv[i - 1] * inv[i] % MOD;
		}
	}

	// 二項係数計算
	static	long COM(int n, int k){
		if (n < k) return 0;
		if (n < 0 || k < 0) return 0;
		return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
	}








	static int upperbond(int k,ArrayList<Integer> data){		//k以下で最大の値をdataの中から探し、返す二分探索
		if(data == null){
			return -1;
		}
		int max = data.size();
		int min = -1;
		while(max-min > 1){
			int mid = (max+min)/2;
			if(data.get(mid) <= k){
				min = mid;
			}else{
				max = mid;
			}
		}

		
//		if(min != -1){
//			min = data.get(min);
//		}
		
//		System.out.println(max);
		return min;					//indexを返している
	}

	static int lowerbond(int k,ArrayList<Integer> data){		//k以上で最小の値をdataの中から探し、返す二分探索
		if(data == null){
			return -1;
		}
//		System.out.println("lo");
//		System.out.println("lo");
		int max = data.size();
		int min = -1;

		while(max-min > 1){
			int mid = (max+min)/2;
			if(data.get(mid) >= k){
				max = mid;
			}else{
				min = mid;
			}
		}

		return max;			//indexを返している
	}



	static int gcd(int a,int b){				//最大公約数を返す
		if(b == 0){
			return a;
		}else{
			return gcd(b, a%b);
		}
	}
	static long gcd(long a,long b){
		if(b == 0){
			return a;
		}else{
			return gcd(b, a%b);
		}
	}



	static long lcm (long a, long b) {
		long g = gcd(a,b);
		return a/g*b;
	}




}

class Pair implements Comparable{
	int from;
	int end;
	public Pair(int from,int end) {
		this.from = from;
		this.end = end;
		// TODO 自動生成されたコンストラクター・スタブ
	}

	@Override
	public int compareTo(Object other) {
		Pair otherpair = (Pair)other;

		return  from - otherpair.from;
	}








}





/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