JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

JavaScript

var saveArray = new Array();
	saveArray[0] = false;
	saveArray[1] = false;

	$(document).ready(function(){

		$(document).keydown(function (f){
			if (f.keyCode == 16) {
				saveArray[0] = true;
			}
		});

		$(document).keyup(function (g){
			if(g.which == 16){
				saveArray[0] = false;
			}
		});

		$(document).keydown(function (h){
			if (h.keyCode == 83) {
				saveArray[1] = true;
				if(saveArray[0] == true && saveArray[1] == true){
					saveArray[0] = false;
					saveArray[1] = false;
					keypressSaveFunction();
				}
			}
		});

		$(document).keyup(function (i){
			if (i.which == 83) {
				saveArray[1] = false;
			}
		});
	});

		function keypressSaveFunction(){
            alert("test");
		}