Showing multiple markers on google maps

Showing multiple markers on google maps

My location finder is showing multiple markers, but i don't want that. I'm
not that good with the Google API, so i hope you can help me.
People need to fill in their address, and then he need to show the
location. Without showing multiple markers. (only one)
Here is the JS:
var geocoder;
var map;
function initialize() {
geocoder = new google.maps.Geocoder();
var latlng = new google.maps.LatLng(52.132633, 5.291266);
var myOptions = {
zoom: 7,
center: latlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
};
map = new google.maps.Map(document.getElementById("map_canvas"),
myOptions);
}
function codeAddress() {
var sAddress = document.getElementById("inputTextAddress").value;
document.getElementById("map_canvas").style.removeProperty('display');
geocoder.geocode( { 'address': sAddress}, function(results, status) {
if (status == google.maps.GeocoderStatus.OK) {
map.setCenter(results[0].geometry.location);
map.setZoom(10);
var marker = new google.maps.Marker({
map: map,
position: results[0].geometry.location
});
} else {
alert("Helaas, er is iets fout gegaan. Foutcode: " + status);
}
});
}