JSFiddle - React, Tailwind, and code Playground

by Erik East

HTML

<h2>Module 04</h2>
<h3>Assignment 1</h3>
<p>Input a number: <input type='text' style="width: 50px;" id='theoutput' onkeypress='captureEnter(event);'></p>
<p id="demo"></p>

JavaScript

var theStack = [];
var input = '';

function captureEnter(e){
        if(e.keyCode === 13){
            stackComputer();
        }
        return false;
}
function stackComputer(){
    var theinput = document.getElementById('theoutput').value;
    if(!isNaN(parseInt(theinput, 10))){
        theStack.push(theinput);
    }//if
	else if(theinput=='+'){
        var num1 = theStack.pop();
        var num2 = theStack.pop();
        var add = parseInt(num1) + parseInt(num2);
        theStack.push(add);
    }//else if addition
	else if(theinput=='-'){
        var num3 = theStack.pop();
        var num4 = theStack.pop();
        var subtract =  num3 - num4;
        theStack.push(subtract);
    }//else if subtraction
	else if(theinput=='*'){
        var num5 = theStack.pop();
        var num6 = theStack.pop();
        var multiply = num5 * num6;
        theStack.push(multiply);
    }//else if mutliplication
	else if(theinput=='/'){
        var num7 = theStack.pop();
        var num8 = theStack.pop();
        var divide = num7 / num8;
        theStack.push(divide);
    }//else if division
    document.getElementById('theoutput').value = '';
    displayStack();
}//function stackComputer

function displayStack (){
    document.getElementById('demo').innerHTML = '' ;
    for(var i = 0; i < theStack.length; i++){
		document.getElementById('demo').innerHTML += theStack[i] + ' | ';
    }//for loop output
}//function printStack