Module1 walkthrough

by Ryan Brown

HTML

<div id="operations1"></div>
<br>
<div id="operations2"></div>
<br>

<div id="find"></div>
<br>
<div id="find-option"></div>
<br>

<div id="form-array">
  <form>
    Index:
    <br>
    <input type="text" name="index" id="index" value="3">
    <br> Number:
    <br>
    <input type="text" name="number" id="number" value="0">
    <br>
    <br>
  </form>
  <input type="submit" id="click" value="Update Array">
  <br>
  <br>
</div>
<div id="updated-array"></div>

CSS

#click {
  font-size: inherit;
  color: #FFF;
  background-color: #000;
  width: 10em;
  height: 3em;
}

JavaScript

//create a program that will instantiate an integer array of size 1000
var array = new Array(1000); //O(1) constant

//when 'Update Array' is clicked call myFormSubmit function
document.getElementById("click").onclick = function() {
  myFormSubmit()
}; //O(1)

//form function called and stores form input as variables
function myFormSubmit() { //O(1)
  var index_entered = document.getElementById("index").value; //O(1)
  var number_entered = document.getElementById("number").value; //O(1)
  document.getElementById('updated-array').innerHTML = InsertIntoArray(array, index_entered, number_entered); //O(1)
}

function InsertIntoArray(array, index, number) { //O(1)
  //Fill each array element with a random integer between 1 and 100. 

  //add a number between 1 and 100 to each element in array
  // 100 gives random inclusive of 0..99
  // +1 makes inclusive of 100
  for (var a = 0; a < array.length; a++) { // O(N) //do multiple times // 2002
    //array[a] = a;
    array[a] = Math.floor((Math.random() * 100) + 1); // O(1)  //1000        
  }

  //remove last element from array
  //array.pop(); // O(n)

  //alternate with splice (index, how many) index-1 is last index
  //array.splice(-1,1); // O(n)

  //alternate using array.length
  array.length = array.length - 1; // O(1)

  //replace element (index, how many items to remove starting at index, values to add)
  array.splice(index, 0, number); // O(n)

  //accept user input as number
  array[index] = number; // O(1)

  //printing output
  var updated_array = "";
  for (i = 0; i < array.length; i++) { // O(N) //2002
    updated_array += array[i] + " = Value of array index " + i + "<br>"; // O(1) //1000
  }
  return document.getElementById('updated-array').innerHTML = updated_array; // O(1)
}

function SearchArray(array, find) { // O(1) 
  for (var a = 0; a < array.length; a++) { // O(N) //2002
    array[a] = Math.floor((Math.random() * 100) + 1); // O(1)          
  }
  a = array.indexOf(find); // O(n)
  return a != -1...