将谷歌地图标记颜色更改为我选择的颜色

function initialize() {
  var latlng = new google.maps.LatLng(47.605, -122.2);
  var myOptions = {
    zoom: 10,
    center: latlng,
    mapTypeId: google.maps.MapTypeId.ROADMAP
  };
  var map = new google.maps.Map(document.getElementById("map_canvas"),
    myOptions);
  var marker = new google.maps.Marker({
    map: map,
    position: latlng,
    icon: pinSymbol('red')
  });

  var marker1 = new google.maps.Marker({
    map: map,
    position: new google.maps.LatLng(47.5, -122.0),
    icon: pinSymbol('#7CFC00')
  });
  var marker2 = new google.maps.Marker({
    map: map,
    position: new google.maps.LatLng(47.6, -122.3),
    icon: pinSymbol('orange')
  });
  var marker3 = new google.maps.Marker({
    map: map,
    position: new google.maps.LatLng(47.7, -122.1),
    icon: pinSymbol('yellow')
  });
}

function pinSymbol(color) {
  return {
    path: 'M 0,0 C -2,-20 -10,-22 -10,-30 A 10,10 0 1,1 10,-30 C 10,-22 2,-20 0,0 z',
    fillColor: color,
    fillOpacity: 1,
    strokeColor: '#000',
    strokeWeight: 2,
    scale: 1
  };
}

google.maps.event.addDomListener(window, 'load', initialize);

html,
body,
#map_canvas {
  height: 500px;
  width: 500px;
  margin: 0px;
  padding: 0px
}

<script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk"></script>
<div id="map_canvas" style="width:750px; height:450px; border: 2px solid #3872ac;"></div>