heapsort.html

---
layout: default
---
<h1>Heap Sort</h1>
<canvas id="canvas" width="500" height="500"></canvas>
<script type="text/javascript">
  var	c = document.getElementById("canvas");
  var ctx = c.getContext("2d");
  var w = c.width;
  var h = c.height;

  var data;
  var pq;

  function init() {
    data = Array(100);
    for(var i = 0; i < data.length; i++) {
      data[i] = Math.random()*(h-20) + 10 | 0;
    }
    pq = new PriorityQueue(data, function(a,b){return a > b;});
  }

  function draw() {
    ctx.fillStyle = "#ffffff";
    ctx.fillRect(0,0,w,h);

    var oy = h-10;
    var ox = 2;
    var dx = (w-ox*(data.length-1))/data.length;

    ctx.fillStyle = "#000000";
    for(var i = 0; i < data.length; ++i) {
      ctx.fillRect((ox+dx)*i,oy, dx, -data[i]);
    }
  }

  var first = true;
  function enterFrame() {
    if(!pq.length) return;
    if(!first)	pq.removeTop();
    draw();
    first = false;
  }

  init();

  setInterval(enterFrame, 20);
</script>