Language: Java

import java.util.*;

public class Main{
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        
        int N = sc.nextInt();

        String[] s = new String[N];
        for(int i = 0; i < N; i++)
            s[i] = sc.next();       
        
        int count = 0;
        int[][] str = new int[N][26];
        String[] str2 = new String[N];
        for(int j = 0; j < N; j++){
            for(int i = 0; i < s[j].length; i++){
                if(s[j].charAt(i) == 'a')
                    str[j][0]++;
                if(s[j].charAt(i) == 'b')
                    str[j][1]++;
                if(s[j].charAt(i) == 'c')
                    str[j][2]++;
                if(s[j].charAt(i) == 'd')
                    str[j][3]++;
                if(s[j].charAt(i) == 'e')
                    str[j][4]++;
                if(s[j].charAt(i) == 'f')
                    str[j][5]++;
                if(s[j].charAt(i) == 'g')
                    str[j][6]++;
                if(s[j].charAt(i) == 'h')
                    str[j][7]++;
                if(s[j].charAt(i) == 'i')
                    str[j][8]++;
                if(s[j].charAt(i) == 'j')
                    str[j][9]++;
                if(s[j].charAt(i) == 'k')
                    str[j][10]++;
                if(s[j].charAt(i) == 'l')
                    str[j][11]++;
                if(s[j].charAt(i) == 'm')
                    str[j][12]++;
                if(s[j].charAt(i) == 'n')
                    str[j][13]++;
                if(s[j].charAt(i) == 'o')
                    str[j][14]++;
                if(s[j].charAt(i) == 'p')
                    str[j][15]++;
                if(s[j].charAt(i) == 'q')
                    str[j][16]++;
                if(s[j].charAt(i) == 'r')
                    str[j][17]++;
                if(s[j].charAt(i) == 's')
                    str[j][18]++;
                if(s[j].charAt(i) == 't')
                    str[j][19]++;
                if(s[j].charAt(i) == 'u')
                    str[j][20]++;
                if(s[j].charAt(i) == 'v')
                    str[j][21]++;
                if(s[j].charAt(i) == 'w')
                    str[j][22]++;
                if(s[j].charAt(i) == 'x')
                    str[j][23]++;
                if(s[j].charAt(i) == 'y')
                    str[j][24]++;
                if(s[j].charAt(i) == 'z')
                    str[j][25]++; 
            }
            str2[j] = Arrays.toString(str[j]);
        }

        
        Map<String, Integer> map = new HashMap<>();
        for(int i = 0; i < N; i++){
            if(map.containsKey(str2[i])){
                map.put(str2[i], map.get(str2[i])+1);
            } else {
                map.put(str2[i], 1);
            }
        }

        for( int val: map.values()){
            count += comb2(val);
        }
        System.out.println(count);
        sc.close();
    }

    static long comb2(int n){
        return n * (n-1) / 2;
    }
}


Compiler output:
Main.java:17: error: cannot find symbol
            for(int i = 0; i < s[j].length; i++){
                                   ^
  symbol:   variable length
  location: class String
1 error