import java.util.*; 


public class Main
 {
	public static void main (String[] args)
	 {
	    Scanner in = new Scanner(System.in);
	    int n = in.nextInt();
	    in.nextLine();
	    String[] A = new String[n];
	    
	    
	    for(int i=0;i<n;i++) {
	    	A[i] = in.nextLine();
	    	
	    }
	    
	    for(int i=0;i<n;i++) {
	    	char[] stringArray = A[i].toCharArray();
	    	Arrays.sort(stringArray);
	    	A[i] = new String(stringArray);
	    }
	    
	    Arrays.sort(A);
	    long ans = 0;
	    
	    long count = 1;
	    String current = "";
	    for(int i=0;i<n;i++) {
	    	if(!current.equals(A[i])) {
	    		ans += count*(count-1)/2;
	    		count = 1;
	    		
	    		
	    		
	    	}
	    	else {
	    		count++;
	    	}
	    	current = A[i];
	    	
	    }
	    ans+= count*(count-1)/2;
	   
	    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