A5(forked from a4)

by Ebony McCoy

HTML

<br>
<br/>Enter Content Here:
<input type="textbox" id="_content" />

<input type="button" value="Push Node to List" onclick= isNumber() />
<input type="button" value="Pop Results" onclick="pop()" />
<br/>

<p id="output"></p>

JavaScript

var stack = new Stack();

function Node() {
  this.content = _content;
  this.last = null;
  this.next = null;
  return this;
}

function Stack() {
  this.bottom = null;
  this.top = null;
  this.length = 0;


  Stack.prototype.push = function(_content) {
    var node = new Node(_content);
    if (this.bottom === null) {
      // if there is not head,set node to heade of list
      this.bottom = node;
      this.length += 1;
      return node;
    }


  };
  LinkedList.prtototype.pop = function() {
    if (this.bottom === null) {
      alert("This stack is empty!!");
      return null;
    }
    if (this.bottom === this.top) {
      this.bottom = null;
      this.top = null;
      return this.top;
    }

    var a = this.bottom;
    this.bottom = this.bottom.last;
    this.bottom.next = null;
    return a;
  };

  Stack.prototype.toString = function() {
    var str = "";
    var node = this.head;

    while (node !== null) {
      str += node.content + ":";
      node = node.next;
    }
    return str;
  };
  var stack = new Stack();

  function isNumber(_content) {

    var i = document.getElementById('userinput').content;
    if (isNaN(i)) {
      alert('Input must only be a number or an operator (+, -, *, /)');
      document.getElementById('userinput').content = '';

      return false;
    }

    function pop() {
      document.getElementById('output1').innerHTML = "" + Stack.toString();
      Stack.pop();

    }

//   function isOperator(_content) {
   var x, y, result;
      if (Stack.top.content == "+") {
        x = parseInt(Stack.bottom._content);
        y = parseInt(Stack.bottom.next);
        result(x + y);
      } else if (Stack.top.content == "-") {
        x = parseInt(Stack.bottom._content);
        y = parseInt(Stack.bottom.next);
        result(x - y);
     } else if (Stack.top.content == "*") {
         x = parseInt(Stack.bottom._content);
         y = parseInt(Stack.bottom.next);
         result(x * y);
       } else if (top.content == "/")...