splay.js 1.3 KB

12345678
  1. /*
  2. Copyright (c) 2004-2009, The Dojo Foundation All Rights Reserved.
  3. Available via Academic Free License >= 2.1 OR the modified BSD license.
  4. see: http://dojotoolkit.org/license for details
  5. */
  6. if(!dojo._hasResource["dojox.encoding.compression.splay"]){dojo._hasResource["dojox.encoding.compression.splay"]=true;dojo.provide("dojox.encoding.compression.splay");dojo.require("dojox.encoding.bits");dojox.encoding.compression.Splay=function(n){this.up=new Array(2*n+1);this.left=new Array(n);this.right=new Array(n);this.reset();};dojo.extend(dojox.encoding.compression.Splay,{reset:function(){for(var i=1;i<this.up.length;this.up[i]=Math.floor((i-1)/2),++i){}for(var i=0;i<this.left.length;this.left[i]=2*i+1,this.right[i]=2*i+2,++i){}},splay:function(i){var a=i+this.left.length;do{var c=this.up[a];if(c){var d=this.up[c];var b=this.left[d];if(c==b){b=this.right[d];this.right[d]=a;}else{this.left[d]=a;}this[a==this.left[c]?"left":"right"][c]=b;this.up[a]=d;this.up[b]=c;a=d;}else{a=c;}}while(a);},encode:function(_1,_2){var s=[],a=_1+this.left.length;do{s.push(this.right[this.up[a]]==a);a=this.up[a];}while(a);this.splay(_1);var l=s.length;while(s.length){_2.putBits(s.pop()?1:0,1);}return l;},decode:function(_3){var a=0;do{a=this[_3.getBits(1)?"right":"left"][a];}while(a<this.left.length);a-=this.left.length;this.splay(a);return a;}});}