import java.util.*;
import java.io.*;
public class Main{
	public static void main(String sp[])throws IOException{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		ArrayList<String> al = new ArrayList<>();
		for(int i=0;i<n;i++){
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		}
		Collections.sort(al);
		long count=0;
		long total=0;
		for(int i=0;i<n-1;i++){
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		}
		total++;
		count+=((total*(total-1))/2);
		System.out.println(count);
		
	}
	
	
	static class Reader
		{
			final private int BUFFER_SIZE = 1 << 16;
			private DataInputStream din;
			private byte[] buffer;
			private int bufferPointer, bytesRead;
			BufferedReader br;
			public Reader()
			{
				din = new DataInputStream(System.in);
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
				br = new BufferedReader(new InputStreamReader(System.in));
			}
	 
			public Reader(String file_name) throws IOException
			{
				din = new DataInputStream(new FileInputStream(file_name));
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
			}
	 
			public String readLine() throws IOException
			{
				byte[] buf = new byte[64]; // line length
				int cnt = 0, c;
				while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				}
				return new String(buf, 0, cnt);
			}
			
			
			
	 
			public int nextInt() throws IOException
			{
				int ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9');
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			public long nextLong() throws IOException
			{
				long ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
				if (neg)
					return -ret;
				return ret;
			}
	 
			public double nextDouble() throws IOException
			{
				double ret = 0, div = 1;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
	 
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
	 
				if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				}
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			private void fillBuffer() throws IOException
			{
				bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
				if (bytesRead == -1)
					buffer[0] = -1;
			}
	 
			private byte read() throws IOException
			{
				if (bufferPointer == bytesRead)
					fillBuffer();
				return buffer[bufferPointer++];
			}
			StringTokenizer st;
			String next() {
				while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				}
				return st.nextToken();
			}
	 
	 
			public void close() throws IOException
			{
				if (din == null)
					return;
				din.close();
			}
		}
} import java.util.*; util.* java import java.io.*; io.* java public class Main{
	public static void main(String sp[])throws IOException{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		ArrayList<String> al = new ArrayList<>();
		for(int i=0;i<n;i++){
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		}
		Collections.sort(al);
		long count=0;
		long total=0;
		for(int i=0;i<n-1;i++){
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		}
		total++;
		count+=((total*(total-1))/2);
		System.out.println(count);
		
	}
	
	
	static class Reader
		{
			final private int BUFFER_SIZE = 1 << 16;
			private DataInputStream din;
			private byte[] buffer;
			private int bufferPointer, bytesRead;
			BufferedReader br;
			public Reader()
			{
				din = new DataInputStream(System.in);
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
				br = new BufferedReader(new InputStreamReader(System.in));
			}
	 
			public Reader(String file_name) throws IOException
			{
				din = new DataInputStream(new FileInputStream(file_name));
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
			}
	 
			public String readLine() throws IOException
			{
				byte[] buf = new byte[64]; // line length
				int cnt = 0, c;
				while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				}
				return new String(buf, 0, cnt);
			}
			
			
			
	 
			public int nextInt() throws IOException
			{
				int ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9');
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			public long nextLong() throws IOException
			{
				long ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
				if (neg)
					return -ret;
				return ret;
			}
	 
			public double nextDouble() throws IOException
			{
				double ret = 0, div = 1;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
	 
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
	 
				if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				}
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			private void fillBuffer() throws IOException
			{
				bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
				if (bytesRead == -1)
					buffer[0] = -1;
			}
	 
			private byte read() throws IOException
			{
				if (bufferPointer == bytesRead)
					fillBuffer();
				return buffer[bufferPointer++];
			}
			StringTokenizer st;
			String next() {
				while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				}
				return st.nextToken();
			}
	 
	 
			public void close() throws IOException
			{
				if (din == null)
					return;
				din.close();
			}
		}
} Main public static void main(String sp[])throws IOException{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		ArrayList<String> al = new ArrayList<>();
		for(int i=0;i<n;i++){
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		}
		Collections.sort(al);
		long count=0;
		long total=0;
		for(int i=0;i<n-1;i++){
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		}
		total++;
		count+=((total*(total-1))/2);
		System.out.println(count);
		
	} main {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		ArrayList<String> al = new ArrayList<>();
		for(int i=0;i<n;i++){
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		}
		Collections.sort(al);
		long count=0;
		long total=0;
		for(int i=0;i<n-1;i++){
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		}
		total++;
		count+=((total*(total-1))/2);
		System.out.println(count);
		
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc ArrayList<String> al = new ArrayList<>(); al new ArrayList<>() for(int i=0;i<n;i++){
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		} int i=0; int i=0; i 0 i<n i n i++ i++ i {
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		} {
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		} String temp = sc.next(); temp sc.next() sc.next sc char arr[] = temp.toCharArray(); arr temp.toCharArray() temp.toCharArray temp Arrays.sort(arr) Arrays.sort Arrays arr String st = new String(arr); st new String(arr) al.add(st) al.add al st Collections.sort(al) Collections.sort Collections al long count=0; count 0 long total=0; total 0 for(int i=0;i<n-1;i++){
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		} int i=0; int i=0; i 0 i<n-1 i n-1 n 1 i++ i++ i {
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		} {
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		} if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			} al.get(i).equals(al.get(i+1)) al.get(i).equals al.get(i) al.get al i al.get(i+1) al.get al i+1 i 1 {
				total++;
			} total++ total {
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			} total+=1 total 1 count+=((total*(total-1))/2) count ((total*(total-1))/2) (total*(total-1)) total (total-1) total 1 2 total=0 total 0 total++ total count+=((total*(total-1))/2) count ((total*(total-1))/2) (total*(total-1)) total (total-1) total 1 2 System.out.println(count) System.out.println System.out System System.out count String sp[] sp static class Reader
		{
			final private int BUFFER_SIZE = 1 << 16;
			private DataInputStream din;
			private byte[] buffer;
			private int bufferPointer, bytesRead;
			BufferedReader br;
			public Reader()
			{
				din = new DataInputStream(System.in);
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
				br = new BufferedReader(new InputStreamReader(System.in));
			}
	 
			public Reader(String file_name) throws IOException
			{
				din = new DataInputStream(new FileInputStream(file_name));
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
			}
	 
			public String readLine() throws IOException
			{
				byte[] buf = new byte[64]; // line length
				int cnt = 0, c;
				while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				}
				return new String(buf, 0, cnt);
			}
			
			
			
	 
			public int nextInt() throws IOException
			{
				int ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9');
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			public long nextLong() throws IOException
			{
				long ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
				if (neg)
					return -ret;
				return ret;
			}
	 
			public double nextDouble() throws IOException
			{
				double ret = 0, div = 1;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
	 
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
	 
				if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				}
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			private void fillBuffer() throws IOException
			{
				bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
				if (bytesRead == -1)
					buffer[0] = -1;
			}
	 
			private byte read() throws IOException
			{
				if (bufferPointer == bytesRead)
					fillBuffer();
				return buffer[bufferPointer++];
			}
			StringTokenizer st;
			String next() {
				while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				}
				return st.nextToken();
			}
	 
	 
			public void close() throws IOException
			{
				if (din == null)
					return;
				din.close();
			}
		} Reader final private int BUFFER_SIZE = 1 << 16; BUFFER_SIZE 1 << 16 1 16 private DataInputStream din; din private byte[] buffer; buffer private int bufferPointer bufferPointer bytesRead; bytesRead BufferedReader br; br StringTokenizer st; st public Reader()
			{
				din = new DataInputStream(System.in);
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
				br = new BufferedReader(new InputStreamReader(System.in));
			} Reader {
				din = new DataInputStream(System.in);
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
				br = new BufferedReader(new InputStreamReader(System.in));
			} din = new DataInputStream(System.in) din new DataInputStream(System.in) buffer = new byte[BUFFER_SIZE] buffer new byte[BUFFER_SIZE] BUFFER_SIZE bufferPointer = bytesRead = 0 bufferPointer bytesRead = 0 bytesRead 0 br = new BufferedReader(new InputStreamReader(System.in)) br new BufferedReader(new InputStreamReader(System.in)) public Reader(String file_name) throws IOException
			{
				din = new DataInputStream(new FileInputStream(file_name));
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
			} Reader {
				din = new DataInputStream(new FileInputStream(file_name));
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
			} din = new DataInputStream(new FileInputStream(file_name)) din new DataInputStream(new FileInputStream(file_name)) buffer = new byte[BUFFER_SIZE] buffer new byte[BUFFER_SIZE] BUFFER_SIZE bufferPointer = bytesRead = 0 bufferPointer bytesRead = 0 bytesRead 0 String file_name file_name public String readLine() throws IOException
			{
				byte[] buf = new byte[64]; // line length
				int cnt = 0, c;
				while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				}
				return new String(buf, 0, cnt);
			} readLine {
				byte[] buf = new byte[64]; // line length
				int cnt = 0, c;
				while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				}
				return new String(buf, 0, cnt);
			} byte[] buf = new byte[64]; buf new byte[64] 64 int cnt = 0 cnt 0 c; c while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				} (c = read()) != -1 (c = read()) c read() read -1 1 {
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				} if (c == '\n')
						break; c == '\n' c '\n' break; buf[cnt++] = (byte) c buf[cnt++] buf cnt++ cnt (byte) c return new String(buf, 0, cnt); new String(buf, 0, cnt) public int nextInt() throws IOException
			{
				int ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9');
	 
				if (neg)
					return -ret;
				return ret;
			} nextInt {
				int ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9');
	 
				if (neg)
					return -ret;
				return ret;
			} int ret = 0; ret 0 byte c = read(); c read() read while (c <= ' ')
					c = read(); c <= ' ' c ' ' c = read() c read() read boolean neg = (c == '-'); neg (c == '-') c '-' if (neg)
					c = read(); neg c = read() c read() read do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9'); (c = read()) >= '0' && c <= '9' (c = read()) >= '0' (c = read()) c read() read '0' c <= '9' c '9' {
					ret = ret * 10 + c - '0';
				} ret = ret * 10 + c - '0' ret ret * 10 + c - '0' ret * 10 + c ret * 10 ret 10 c '0' if (neg)
					return -ret; neg return -ret; -ret ret return ret; ret public long nextLong() throws IOException
			{
				long ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
				if (neg)
					return -ret;
				return ret;
			} nextLong {
				long ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
				if (neg)
					return -ret;
				return ret;
			} long ret = 0; ret 0 byte c = read(); c read() read while (c <= ' ')
					c = read(); c <= ' ' c ' ' c = read() c read() read boolean neg = (c == '-'); neg (c == '-') c '-' if (neg)
					c = read(); neg c = read() c read() read do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9'); (c = read()) >= '0' && c <= '9' (c = read()) >= '0' (c = read()) c read() read '0' c <= '9' c '9' {
					ret = ret * 10 + c - '0';
				} ret = ret * 10 + c - '0' ret ret * 10 + c - '0' ret * 10 + c ret * 10 ret 10 c '0' if (neg)
					return -ret; neg return -ret; -ret ret return ret; ret public double nextDouble() throws IOException
			{
				double ret = 0, div = 1;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
	 
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
	 
				if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				}
	 
				if (neg)
					return -ret;
				return ret;
			} nextDouble {
				double ret = 0, div = 1;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
	 
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
	 
				if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				}
	 
				if (neg)
					return -ret;
				return ret;
			} double ret = 0 ret 0 div = 1; div 1 byte c = read(); c read() read while (c <= ' ')
					c = read(); c <= ' ' c ' ' c = read() c read() read boolean neg = (c == '-'); neg (c == '-') c '-' if (neg)
					c = read(); neg c = read() c read() read do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9'); (c = read()) >= '0' && c <= '9' (c = read()) >= '0' (c = read()) c read() read '0' c <= '9' c '9' {
					ret = ret * 10 + c - '0';
				} ret = ret * 10 + c - '0' ret ret * 10 + c - '0' ret * 10 + c ret * 10 ret 10 c '0' if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				} c == '.' c '.' {
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				} while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					} (c = read()) >= '0' && c <= '9' (c = read()) >= '0' (c = read()) c read() read '0' c <= '9' c '9' {
						ret += (c - '0') / (div *= 10);
					} ret += (c - '0') / (div *= 10) ret (c - '0') / (div *= 10) (c - '0') c '0' (div *= 10) div 10 if (neg)
					return -ret; neg return -ret; -ret ret return ret; ret private void fillBuffer() throws IOException
			{
				bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
				if (bytesRead == -1)
					buffer[0] = -1;
			} fillBuffer {
				bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
				if (bytesRead == -1)
					buffer[0] = -1;
			} bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE) bytesRead din.read(buffer, bufferPointer = 0, BUFFER_SIZE) din.read din buffer bufferPointer = 0 bufferPointer 0 BUFFER_SIZE if (bytesRead == -1)
					buffer[0] = -1; bytesRead == -1 bytesRead -1 1 buffer[0] = -1 buffer[0] buffer 0 -1 1 private byte read() throws IOException
			{
				if (bufferPointer == bytesRead)
					fillBuffer();
				return buffer[bufferPointer++];
			} read {
				if (bufferPointer == bytesRead)
					fillBuffer();
				return buffer[bufferPointer++];
			} if (bufferPointer == bytesRead)
					fillBuffer(); bufferPointer == bytesRead bufferPointer bytesRead fillBuffer() fillBuffer return buffer[bufferPointer++]; buffer[bufferPointer++] buffer bufferPointer++ bufferPointer String next() {
				while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				}
				return st.nextToken();
			} next {
				while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				}
				return st.nextToken();
			} while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				} st == null || !st.hasMoreTokens() st == null st null !st.hasMoreTokens() st.hasMoreTokens() st.hasMoreTokens st {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				} try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					} catch (Exception r) {
						r.printStackTrace();
					} Exception r {
						r.printStackTrace();
					} r.printStackTrace() r.printStackTrace r {
						st = new StringTokenizer(br.readLine());
					} st = new StringTokenizer(br.readLine()) st new StringTokenizer(br.readLine()) return st.nextToken(); st.nextToken() st.nextToken st public void close() throws IOException
			{
				if (din == null)
					return;
				din.close();
			} close {
				if (din == null)
					return;
				din.close();
			} if (din == null)
					return; din == null din null return; din.close() din.close din public class Main{
	public static void main(String sp[])throws IOException{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		ArrayList<String> al = new ArrayList<>();
		for(int i=0;i<n;i++){
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		}
		Collections.sort(al);
		long count=0;
		long total=0;
		for(int i=0;i<n-1;i++){
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		}
		total++;
		count+=((total*(total-1))/2);
		System.out.println(count);
		
	}
	
	
	static class Reader
		{
			final private int BUFFER_SIZE = 1 << 16;
			private DataInputStream din;
			private byte[] buffer;
			private int bufferPointer, bytesRead;
			BufferedReader br;
			public Reader()
			{
				din = new DataInputStream(System.in);
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
				br = new BufferedReader(new InputStreamReader(System.in));
			}
	 
			public Reader(String file_name) throws IOException
			{
				din = new DataInputStream(new FileInputStream(file_name));
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
			}
	 
			public String readLine() throws IOException
			{
				byte[] buf = new byte[64]; // line length
				int cnt = 0, c;
				while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				}
				return new String(buf, 0, cnt);
			}
			
			
			
	 
			public int nextInt() throws IOException
			{
				int ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9');
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			public long nextLong() throws IOException
			{
				long ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
				if (neg)
					return -ret;
				return ret;
			}
	 
			public double nextDouble() throws IOException
			{
				double ret = 0, div = 1;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
	 
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
	 
				if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				}
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			private void fillBuffer() throws IOException
			{
				bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
				if (bytesRead == -1)
					buffer[0] = -1;
			}
	 
			private byte read() throws IOException
			{
				if (bufferPointer == bytesRead)
					fillBuffer();
				return buffer[bufferPointer++];
			}
			StringTokenizer st;
			String next() {
				while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				}
				return st.nextToken();
			}
	 
	 
			public void close() throws IOException
			{
				if (din == null)
					return;
				din.close();
			}
		}
} public class Main{
	public static void main(String sp[])throws IOException{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		ArrayList<String> al = new ArrayList<>();
		for(int i=0;i<n;i++){
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		}
		Collections.sort(al);
		long count=0;
		long total=0;
		for(int i=0;i<n-1;i++){
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		}
		total++;
		count+=((total*(total-1))/2);
		System.out.println(count);
		
	}
	
	
	static class Reader
		{
			final private int BUFFER_SIZE = 1 << 16;
			private DataInputStream din;
			private byte[] buffer;
			private int bufferPointer, bytesRead;
			BufferedReader br;
			public Reader()
			{
				din = new DataInputStream(System.in);
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
				br = new BufferedReader(new InputStreamReader(System.in));
			}
	 
			public Reader(String file_name) throws IOException
			{
				din = new DataInputStream(new FileInputStream(file_name));
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
			}
	 
			public String readLine() throws IOException
			{
				byte[] buf = new byte[64]; // line length
				int cnt = 0, c;
				while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				}
				return new String(buf, 0, cnt);
			}
			
			
			
	 
			public int nextInt() throws IOException
			{
				int ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9');
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			public long nextLong() throws IOException
			{
				long ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
				if (neg)
					return -ret;
				return ret;
			}
	 
			public double nextDouble() throws IOException
			{
				double ret = 0, div = 1;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
	 
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
	 
				if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				}
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			private void fillBuffer() throws IOException
			{
				bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
				if (bytesRead == -1)
					buffer[0] = -1;
			}
	 
			private byte read() throws IOException
			{
				if (bufferPointer == bytesRead)
					fillBuffer();
				return buffer[bufferPointer++];
			}
			StringTokenizer st;
			String next() {
				while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				}
				return st.nextToken();
			}
	 
	 
			public void close() throws IOException
			{
				if (din == null)
					return;
				din.close();
			}
		}
} Main
import java.util.*;
import java.io.*;
public class Main{
	public static void main(String sp[])throws IOException{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		ArrayList<String> al = new ArrayList<>();
		for(int i=0;i<n;i++){
			String temp = sc.next();
			char arr[] = temp.toCharArray();
			Arrays.sort(arr);
			String st = new String(arr);
			al.add(st);
		}
		Collections.sort(al);
		long count=0;
		long total=0;
		for(int i=0;i<n-1;i++){
			if(al.get(i).equals(al.get(i+1))){
				total++;
			}else{
				total+=1;
				count+=((total*(total-1))/2);
				total=0;
			}
		}
		total++;
		count+=((total*(total-1))/2);
		System.out.println(count);
		
	}
	
	
	static class Reader
		{
			final private int BUFFER_SIZE = 1 << 16;
			private DataInputStream din;
			private byte[] buffer;
			private int bufferPointer, bytesRead;
			BufferedReader br;
			public Reader()
			{
				din = new DataInputStream(System.in);
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
				br = new BufferedReader(new InputStreamReader(System.in));
			}
	 
			public Reader(String file_name) throws IOException
			{
				din = new DataInputStream(new FileInputStream(file_name));
				buffer = new byte[BUFFER_SIZE];
				bufferPointer = bytesRead = 0;
			}
	 
			public String readLine() throws IOException
			{
				byte[] buf = new byte[64]; // line length
				int cnt = 0, c;
				while ((c = read()) != -1)
				{
					if (c == '\n')
						break;
					buf[cnt++] = (byte) c;
				}
				return new String(buf, 0, cnt);
			}
			
			
			
	 
			public int nextInt() throws IOException
			{
				int ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				} while ((c = read()) >= '0' && c <= '9');
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			public long nextLong() throws IOException
			{
				long ret = 0;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
				if (neg)
					return -ret;
				return ret;
			}
	 
			public double nextDouble() throws IOException
			{
				double ret = 0, div = 1;
				byte c = read();
				while (c <= ' ')
					c = read();
				boolean neg = (c == '-');
				if (neg)
					c = read();
	 
				do
				{
					ret = ret * 10 + c - '0';
				}
				while ((c = read()) >= '0' && c <= '9');
	 
				if (c == '.')
				{
					while ((c = read()) >= '0' && c <= '9')
					{
						ret += (c - '0') / (div *= 10);
					}
				}
	 
				if (neg)
					return -ret;
				return ret;
			}
	 
			private void fillBuffer() throws IOException
			{
				bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
				if (bytesRead == -1)
					buffer[0] = -1;
			}
	 
			private byte read() throws IOException
			{
				if (bufferPointer == bytesRead)
					fillBuffer();
				return buffer[bufferPointer++];
			}
			StringTokenizer st;
			String next() {
				while (st == null || !st.hasMoreTokens()) {
					try {
						st = new StringTokenizer(br.readLine());
					} catch (Exception r) {
						r.printStackTrace();
					}
				}
				return st.nextToken();
			}
	 
	 
			public void close() throws IOException
			{
				if (din == null)
					return;
				din.close();
			}
		}
}