ajax_data.php

<?php
session_start();
include('db.php');

if(isset($_POST['data'])) {
    $list = isset($_SESSION['strtpnt1']) ? $_SESSION['strtpnt1'] : [];
    $list[] = $_POST['data'];
    $_SESSION['strtpnt1'] = $list;
}
$startpoint= (implode(',',$_SESSION['strtpnt1']));echo "valar morghulis";
print_r($startpoint);
?>
		<td id="td12" class="hc">       
			<select name="destination" id="destination" onChange="ajaxcall1(this.value)" class="inp_bx"> 
					<option value="">Select a Destination</option>
					<?php 
					$sql21 = "select start from tbl_place where start NOT IN('".$startpoint."')";
					$retval21 = mysql_query($sql21, $conn );
					if(! $retval21 )
					{
						die('Could not get data: ' . mysql_error());
						echo 'Could not get data: ' . mysql_error();
					}
						while($row = mysql_fetch_assoc($retval21,MYSQL_ASSOC)){ $dest= $row['start'];?>	
						<option value="<?php echo $dest;?>"><?php echo $dest;?></option>
						<?php } ?>
			</select>
			<?php echo "valar morghulis saSAsAS";print_r($_SESSION['strtpnt1']);?>
		</td>

home.php

<!--1st select box-->
<td class="h_c">
<select name="strtpnt" id="strtpnt"  class="inp_bx" onChange="ajaxcall(this.value)">  
	<option>-Select-</option>
		<?php 			  
			$sql = "select distinct(start) from tbl_place";
			$retval = mysql_query($sql, $conn );
		  while($row = mysql_fetch_assoc($retval,MYSQL_ASSOC)){ $strtpnt= $row['start'];?>	
				<option value="<?php echo $strtpnt;?>"><?php echo $strtpnt;?></option>
		<?php } ?>
</select>

<!--2nd select box--><td class="hc">
<select name="destination" id="destination" class="inp_bx"> 
	  <option>-Select-</option>
</select></td>

<!--3rd select box-->
<select name="duration" id="duration"  class="inp_bx" onchange="textHint();"> 
		<option value="1">-Select-</option>
			<?php
				$sql = "select distinct(package_type) from tbl_package";
				$retval = mysql_query($sql, $conn );
					while($row = mysql_fetch_assoc($retval,MYSQL_ASSOC)){ $package= $row['package_type'];?>	
					<option value="<?php echo $package?>"><?php echo $package;?></option>
			<?php } ?>
</select>
			<input  name="submit" id="submit" type="submit" class="btn btn-lg btn-info" value="Submit">
///Now the ajax calls
<script type="text/javascript">
	function textHint()
		{
			//alert("valar morghulis .arya");
			var start=$("#strtpnt").val();
			var destin=$("#destination").val();
			var ans=confirm("Do you want to continue touring");
			if(ans)
				{
					alert("Enjoy the tour visiting various places");
					$.post('tour.php', { start:start,destin:destin}, function(response) {
					console.log(response);
					$('.h_c').html(response);
				});
		}
		else
		{
			window.Location="http://localhost/tpc_new/home1.php";
		}
		return false;
	}
	function ajaxcall(type)
				{
					var parameters = 'data='+type;
					var argUrl = 'ajax_data.php';//alert(parameters);	
					$.ajax({
						url: argUrl,
						type: 'POST',
						data: parameters,
						success: function (str) {
							 $(".hc").html(str);	
							alert(parameters);				
							}
						});
				}
	</script>
						

tour.php

<!--page is same as home1.php-->
<div class="col-md-10 col-md-offset-2" >
<h3 style="padding-left:285px;">Enter the Details</h3>
	Starting Point</label><td>:</td><td class="h_c">
	<select name="strtpnt" id="strtpnt"  class="inp_bx" onChange="ajaxcall(this.value,'start1','hc')">  
		<option>-Select-
		</option>
	<option value="<?php echo $destinationpoint;?>"><?php echo $destinationpoint;?></option>
	</select>
	</td></tr>
	
	Destination Point</td><td>:</td><td class="hc">
        <select name="destination" id="destination" onChange="ajaxcall1(this.value)" class="inp_bx"> 
	<option>-Select-</option>
	 </select>
	Duration<td> :</td><td>
        <select name="duration" id="duration"  class="inp_bx" onchange="textHint();"> 
	<option value="1">-Select-</option>
	<?php
		$sql = "select distinct(package_type) from tbl_package";
		$retval = mysql_query($sql, $conn );
		while($row = mysql_fetch_assoc($retval,MYSQL_ASSOC)){ $package= $row['package_type'];?>	
		<option value="<?php echo $package?>"><?php echo $package;?></option>
	<?php } ?>
	</select>
		<input  name="submit" id="submit" type="submit" class="btn btn-lg btn-info" value="Submit">