all sets

by russau

JavaScript

function allsets(letters)
{
    var setsCount = 1 << letters.length;
    document.write(setsCount);
    
    for (var i=0; i<setsCount; i++)
    {
        
        var bitsOn = 0;
        var slider = i;
        var index = 0;
        while (slider > 0)
        {
            if (slider & 1)
            {                

                document.write(letters[index]);
            }
            
            slider = slider >> 1;
            index++;
        }
        document.write('<br/>');
    }
}

allsets(['a','b','c','d']);