factorial of a number

Question

I have the following code but it is not giving perfect result for factorial can u find it out plz

Answer 1

Use loop its easy to implement

function fact(num)
{
    if(num<0)
     return "Undefined";
    var fact=1;
    for(var i=num;i>1;i--)
      fact*=i;
    return fact;
 }