stack_example

by davidjb95

HTML

<p id='output1'></p>
<p id='output2'></p>
<input type="textbox" id="StackName" Value="Put in number or operator" />
<input type="button" id="AddLink" value="Add to Stack" onClick="addStack();" />

JavaScript

function addStack() {
  var value = document.getElementById("StackName").value;

  stack.push(value);
  document.getElementById('output1').innerHTML = 'Add to top of stack ' + stack.toString();
}
var Node = function(_content) {
  this.next = null;
  this.last = null;
  this.content = _content;

}

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

  this.push = function(_content) {
    // No head - create one
    if (this.bottom == null) {
      this.bottom = new Node(_content);
      this.top = this.bottom;
      return this;
    }

    var addedNode = new Node(_content);
    addedNode.last = this.top; // pointer to previous node
    this.top.next = addedNode; // current top points to new
    this.top = addedNode; // which becomes new top
    return this;
  }

  this.pop = function() {
    if (this.bottom == null) {
      alert("The Stack is Empty");
      return null;
    }
    // Case of one node
    if (this.bottom == this.top) {
      // Exercise for students to implement
      alert("You must implement this case");
      return this.top;
    }

    // Now remove top Node
    var a = this.top; // hold value for return
    this.top = this.top.last;
    this.top.next = null;

    return a;
  }

  this.toString = function() {
    var str = "";
    var node = this.bottom;
    var node2 = this.top;
    var operator = new Array('/','*','-','+');
		var i = 0;
    // sees if top content is one of the operators 
    for(i=0;i < operator.length; i++){
    if(node2.content == "/"){
    	alert("it works");
    }
    }
    var test = parseInt(node2.content);
    // if the input is not a number don't accept it
    if(Number.isNaN(test)){
    	stack.pop();
      }
 		document.getElementById('output2').innerHTML =  test + test;
 
    while (node != null) {
      str += node.content + ":";
      node = node.next;
    }
    return str;
   } 
   
}

// Create a Linked List and Add Nodes
var stack = new...