Simple way to get element by id within a div tag?

Question

Please forgive me if I repeat the question.

I have HTML　that all elements inside a div tag has different id, suppose I have already get the reference to the div, is

Answer 1

Sample Html code   
 

        F1 

        F2 

        F3 

        Type 
        A
        B
        C
        
        
    

Javascript

    function  getVal()
    {
        var test = document.getElementById("temp").getElementsByTagName("input");
        alert("Number of Input Elements "+test.length);
        for(var i=0;i