Removing the Duplicates of a String in Java

Problem:

Write a program that read a string str and prints a string obtained from str by removing/ignoring duplicates. For example, if str is abbacdcae, then your program prints abcde. In other words, only the first occurrence of a character is printed.

Solution:

          import java.util.Scanner;

public class lauprob3
{
 public static void main(String[] args) 
 {
  //First off, let's scan our string
   Scanner scan = new Scanner (System.in);
  
     String string = scan.nextLine();
     
     //We're gonna be looping over each character in the String
    for (int x = 0; x < string.length(); x++)
      
         //We're gonna loop over every character of the String
         //that comes after the character from the outer/first loop
         for (int y = x+1; y <= string.length()-1; y++)
         {
             //We're gonna check if any of the characters after x
             //ie the characters from this second loop, are the same as 
             //as x so that we'll remove x's duplicates
             if (string.charAt(x) == string.charAt(y))
             {
                 //If we find that x and y are equal 
                 //then we're going to make our string equal to
                 //itself but without the y character through using
                 //substrings that pass over y
                 //Note: substring(a,b) means from a to b but only including a
                 string = string.substring(0,y)+ string.substring(y+1,string.length());          
                 
                 //We need to get rid of an extra increment because we
                 //deleted a repeated character
                 y--;
             }
         }
     
     System.out.println(string);
 }
}

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