function check1()
{
var a = 10;

disp_a();

function disp_a()
   {
   var a = 20;
   alert("Value of 'a' inside the function " + a);
   }

alert("Value of 'a' outside the function " + a);
}

function check2()
{
var a = 10;

disp_a();

function disp_a()
   {
   a = 20;
   alert("Value of 'a' inside the function " + a);
   }

alert("Value of 'a' outside the function " + a);
}