javascript随机输出0-35里面的7个数字.输出的数不能重复..

<script type="text/javascript">
var arr = new Array();
var num;

for(var i = 0, j; i < 7; i++)
{
num = parseInt(Math.random() * 35);

for(j = 0; j < arr.length; j++)
{
if(arr[j] == num)break;
}

if(j == arr.length)
{
arr[arr.length] = num;
}
else
{
i --;
}
}
document.write(arr.toString());
</script>