Java Program to find all subsets of a string

public class AllSubsets {  
    public static void main(String[] args) {  
  
        String str = "FUN";  
        int len = str.length();  
        int temp = 0;  
        //Total possible subsets for string of size n is n*(n+1)/2  
        String arr[] = new String[len*(len+1)/2];  
  
        //This loop maintains the starting character  
        for(int i = 0; i < len; i++) {  
            //This loop adds the next character every iteration for the subset to form and add it to the array  
            for(int j = i; j < len; j++) {  
                arr[temp] = str.substring(i, j+1);  
                temp++;  
            }  
        }  
  
        //This loop prints all the subsets formed from the string.  
        System.out.println("All subsets for given string are: ");  
        for(int i = 0; i < arr.length; i++) {  
            System.out.println(arr[i]);  
        }  
    }  
}  

Output:

All subsets for given string are:
F
FU
FUN
U
UN
N