Java Program to remove duplicates from a String using Hashing

package practice;

import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.Scanner;

public class RemoveDuplicates {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		System.out.println("Please enter string for test");
		String sampleString = sc.next();

		LinkedHashSet<String> aMap = new LinkedHashSet<String>();
		for (int i = 0; i < sampleString.length(); i++) {

			if (!aMap.contains(String.valueOf(sampleString.charAt(i)))) {
				aMap.add(String.valueOf(sampleString.charAt(i)).toLowerCase());
			}
		}
		Iterator<String> itr = aMap.iterator();
		System.out.println("String After Removing Duplicates");
		while (itr.hasNext()) {
			System.out.print(itr.next());
		}

	}

}

package practice;

import java.util.Iterator;

import java.util.LinkedHashSet;

import java.util.Scanner;

public class RemoveDuplicates {

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

System.out.println("Please enter string for test");

String sampleString = sc.next();

LinkedHashSet<String> aMap = new LinkedHashSet<String>();

for (int i = 0; i < sampleString.length(); i++) {

if (!aMap.contains(String.valueOf(sampleString.charAt(i)))) {

aMap.add(String.valueOf(sampleString.charAt(i)).toLowerCase());

}

Iterator<String> itr = aMap.iterator();

System.out.println("String After Removing Duplicates");

while (itr.hasNext()) {

System.out.print(itr.next());

}

Please enter string for test
Testing
tesing

Please enter string for test

Testing

tesing

Important Notes:

LinkedHashSet is used to preserve the insertion order.
Please debug the code for better understanding.
Converting all character to Lower Case to make program case-insensitive.

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