JSFiddle - React, Tailwind, and code Playground

by Scott Vandervort

HTML

<input id="userInput" placeholder="Your string ..." id="userInput"/>

<button onclick="removeDuplicates( document.getElementById('userInput').value)">Remove Duplicates</button>

<input readonly id="output"></input>

JavaScript

function removeDuplicates ( str ) {

	var map = new Map();
  
  	for (var charIndex = 0; charIndex < str.length; charIndex++) {
    	var char = str.charAt(charIndex);
            
      if (!map.get(char.toUpperCase())) {
      	map.set( char.toUpperCase(), char);
      }
    }
    
    var mapIter = map.entries();
    var result = "";
    var val;
    
    do {
    
    	val = mapIter.next().value;
      
      if (typeof val != 'undefined') {
      	result += val[1];
      }
    }
    while ( typeof val != 'undefined');
    
    //console.log(result);
    
    document.getElementById('output').value = result;

}