Code:
<?php
$timezone = "Asia/Calcutta";
if(function_exists('date_default_timezone_set')) date_default_timezone_set($timezone);
echo date('d/m/Y H:i:s A');
//echo $date = date("Y/m/d H:i:s");echo "\n";
$original=time($timezone);
if(isset($_POST['btn']))
{
$hr=$_POST['hour'];
$min=$_POST['minute'];
$sec=$_POST['second'];
$modified = $original+($hr*60*60)+($min*60)+$sec;