挙動の違い forked from: Math.random() * Number >> 0

/**
 * Copyright bkzen ( http://wonderfl.net/user/bkzen )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/tcVv
 */

// forked from Murai's Math.random() * Number >> 0
// forked from Murai's 0 to .5 to 0
// forked from Murai's Math.random() - Math.random() 
package {
    import flash.display.*;
    import flash.text.*;
    /*
        @author Takashi Murai(KAYAC)
    */
    [SWF(width="400", height="400", frameRate="24", backgroundColor="#FFFFFF")]
    
    public class Main extends Sprite {
          public var txt:TextField;
     
        public function Main() {
            init();         
        }
         
         public function init():void{
             txt = new TextField();
             txt.width = 400;
             txt.height = 400;
             addChild(txt);
             var i:uint=100, n: Number, a: int, b: int, c: int, d: int;
             while(--i){
                 n = Math.random()*5;
                 a = n >> 0;
                 b = Math.floor(n);
                 n = -n;
                 c = n >> 0;
                 d = Math.floor(n);
                 txt.appendText(a + " : " + b + " : "+ (a == b) + " : " + 
                     c + " : " + d + " : " + (c == d) + " : " + n + "\n"
                 );
             }
         }
    }
}