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HTML

              
                
<html>
        <head>
                <title>Simple Page</title>
        </head>
        <body>
          <h1 id="mainHeading"> Interesting Headline</h1>
                <p>This is a VERY  simple html page</p>
                <!--
                <script type="text/javascript" src=“script.js”></script> 

                This source line wasn't working on my desktop, and it doesn't seem to needed here in codepen.io. I fear something may not be working here. -->
        </body>
</html>
              
            
!

CSS

              
                
              
            
!

JS

              
                //1
var name = prompt("What is your name?")
alert("Hello, " + name);

//2
var a;
a = 5
a = 1000000
a = 123.456
a = -500
alert(a);

//3
var phrase = "This is a simple phrase.";
alert(phrase.length);

//4
var name = prompt("What is \nyour name?");
var message = "Hello,";
alert(message + name);

//conditionals, chapter 4

var a = 5;
var b = 10;

if (a < b){
    alert("Yes a is less than b");
    }

if (a == b){
  alert("Yes, a is equal to b");
}

//else statements

var balance = 5000

if (balance >= 0) {
  alert("Yes, you have money!");
  if (balance >= 10000) {
    alert("The balance is large!")
  }
} else {
  alert("Looks like you're out of money!");
}

//strict equality, using ===

var a = 123;
var b = "123";

//equality check

if (a == b){
  alert("They equal!");
} else {
  alert("They are not equal!");
}
//shows equality. js is being flexible here
//if I make the above ===, different result
if (a === b){
  alert("They equal!");
} else {
  alert("They are not equal!");
}
//for the above, !== strictly not equal also works. 

//switches

var grade = "Premium";

switch ( grade ) {
        case "Regular":
                alert("It's $3.15");
                break; //add this break here to prevent fall through reading of the rest of the switch
        case "Premium":
                alert("It's $3.35");
                break;
        case "Diesel":
                alert("It's $3.47");
                break;
        default:
                alert("That's not a valid grade");
}

//time to take a look at functions

function myFunction(){
        var a = 5;
        var b = 10;
        var c = 20;
        var d = a + b + c;
        alert("The value of d is: " + d);
}

myFunction()

// parameterize functions

//parameterize a and b

function addTwoNumbers(a,b)        {
        var result = a + b;
        alert(result);
}

//when calling, function expects values for the a and b buckets. 
//we can create variables within, or, we can give values when we call the function.

addTwoNumbers(5,10);

//check this out

function addTwoNumbers(a,b)        {
        var result = a + b;
        return result; // return produces the value and jumps you right out of block
}

addTwoNumbers(5,10);

//now, let's store multiple iterations of the function call

//...but, this works when you call the function multiple times, and you want to store multiple values

function addTwoNumbers(a,b)        {
        var result = a + b;
        return result;                                       
}

var x = addTwoNumbers(5,10);
        alert(x);
var y = addTwoNumbers(10,20);
        alert(y);
var z = addTwoNumbers(100,200);
        alert(z);

//writing an iterative loop

var amount = 0;

//create the index
var i = 1;

//check condition
while ( i < 10 ) {
        amount = amount + 100;
        //iterate index
        i++;
}

alert("The value is " + amount);

//regular expressions
//Next we need to test our regex object.

//var myRE = new RegExp("hello");
//var myString = "Does this sentence have the word hello in it?";

//if ( myRE.test(MyString) ) //
        //alert("Yes");
//

//right now we return a string, Yes, but regex has other methods to return more complex objects
//!!!!I can't seem to get the above to work. Wierd

var myArray = [10,20,"test","TRUE",99]

var i = 0;

while ( i < myArray.length ) {
        ///...
        ///...
alert("The value is:" + myArray[i]);

i++;
} 
  
//another example of iterating through an array

var myArray = [500,500,500,500,500]

var total = 0

for ( var i = 0; i < myArray.length; i++ ) {
        //add the durrent element to the total
        total = total + myArray[i];
}

//after we're done with the loop
alert("The total is: " + total);


              
            
!
999px

Console