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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

<h1><a href="https://www.freecodecamp.org/challenges/show-national-contiguity-with-a-force-directed-graph" target="_blank">Show National Contiguity with a Force Directed Graph</a></h1>
    <p><a href="https://youtu.be/cJ6NdluzEG8" target="_blank">Watch this tutorial</a></p>

<!-- Footer-->
<div class="row text-center">
			<div class="col-xs-12">
				<div class="tableFooter">
				  <!-- for footer -->
      <div class="col-xs-6">
      <h5><a href="http://www.eleftheriabatsou.com" target="_blank">Eleftheria</a> | <a href="https://codepen.io/EleftheriaBatsou" target="_blank">Projects</a> | <a href="https://www.youtube.com/channel/UCC-WwYv3DEW7Nkm_IP6VeQQ" target="_blank"> Coding videos </a></h5>
      <!-- social media -->
      <div class="col-xs-6 text-primary">
        <a href="https://twitter.com/BatsouElef" target="_blank">
     <img class="footerSvg"src="https://image.flaticon.com/icons/svg/60/60580.svg" 
      style="text-align:center" alt="twitter"> 
         <a href="https://github.com/EleftheriaBatsou" target="_blank">
     <img class="footerSvg" src="https://image.flaticon.com/icons/svg/25/25657.svg" 
      style="text-align:center" alt="github"> 
        <a href="https://www.youtube.com/channel/UCC-WwYv3DEW7Nkm_IP6VeQQ" target="_blank">
     <img class="footerSvg" src="https://image.flaticon.com/icons/svg/25/25312.svg" 
       style="text-align:center" alt="youtube"> 
    <!-- end footer -->
<!-- end of Footer -->

<!-- Force directed graph -->
<div id='container'>
  <div id='graph'>
    <div id='flags'></div>


              body { background-color:lightgray; }

h1, h3, p { text-align:center; }

#container { margin: auto; }

.link { stroke: red; }

#flags {
  position: absolute;

* find the flag-sprite here: https://www.flag-sprites.com/
* create an image and downlaod the file...
* You don't have to upload your own image, 
* you can simply right click on the flag-sprites's image 
* and select copy image address.
* In flags.css (from the file you download) you can copy-paste the .flag.flag-ad section

.flag {
	width: 16px;
	height: 11px;
  position: absolute;
	background: url(https://media.flag-sprites.com/veowpp/flags.png) no-repeat;

.flag.flag-ad {background-position: -16px 0}
.flag.flag-ae {background-position: -32px 0}
.flag.flag-af {background-position: -48px 0}
.flag.flag-ag {background-position: -64px 0}
.flag.flag-ai {background-position: -80px 0}
.flag.flag-al {background-position: -96px 0}
.flag.flag-am {background-position: -112px 0}
.flag.flag-an {background-position: -128px 0}
.flag.flag-ao {background-position: -144px 0}
.flag.flag-ar {background-position: -160px 0}
.flag.flag-as {background-position: -176px 0}
.flag.flag-at {background-position: -192px 0}
.flag.flag-au {background-position: -208px 0}
.flag.flag-aw {background-position: -224px 0}
.flag.flag-az {background-position: -240px 0}
.flag.flag-ba {background-position: 0 -11px}
.flag.flag-bb {background-position: -16px -11px}
.flag.flag-bd {background-position: -32px -11px}
.flag.flag-be {background-position: -48px -11px}
.flag.flag-bf {background-position: -64px -11px}
.flag.flag-bg {background-position: -80px -11px}
.flag.flag-bh {background-position: -96px -11px}
.flag.flag-bi {background-position: -112px -11px}
.flag.flag-bj {background-position: -128px -11px}
.flag.flag-bm {background-position: -144px -11px}
.flag.flag-bn {background-position: -160px -11px}
.flag.flag-bo {background-position: -176px -11px}
.flag.flag-br {background-position: -192px -11px}
.flag.flag-bs {background-position: -208px -11px}
.flag.flag-bt {background-position: -224px -11px}
.flag.flag-bv {background-position: -240px -11px}
.flag.flag-bw {background-position: 0 -22px}
.flag.flag-by {background-position: -16px -22px}
.flag.flag-bz {background-position: -32px -22px}
.flag.flag-ca {background-position: -48px -22px}
.flag.flag-catalonia {background-position: -64px -22px}
.flag.flag-cd {background-position: -80px -22px}
.flag.flag-cf {background-position: -96px -22px}
.flag.flag-cg {background-position: -112px -22px}
.flag.flag-ch {background-position: -128px -22px}
.flag.flag-ci {background-position: -144px -22px}
.flag.flag-ck {background-position: -160px -22px}
.flag.flag-cl {background-position: -176px -22px}
.flag.flag-cm {background-position: -192px -22px}
.flag.flag-cn {background-position: -208px -22px}
.flag.flag-co {background-position: -224px -22px}
.flag.flag-cr {background-position: -240px -22px}
.flag.flag-cu {background-position: 0 -33px}
.flag.flag-cv {background-position: -16px -33px}
.flag.flag-cw {background-position: -32px -33px}
.flag.flag-cy {background-position: -48px -33px}
.flag.flag-cz {background-position: -64px -33px}
.flag.flag-de {background-position: -80px -33px}
.flag.flag-dj {background-position: -96px -33px}
.flag.flag-dk {background-position: -112px -33px}
.flag.flag-dm {background-position: -128px -33px}
.flag.flag-do {background-position: -144px -33px}
.flag.flag-dz {background-position: -160px -33px}
.flag.flag-ec {background-position: -176px -33px}
.flag.flag-ee {background-position: -192px -33px}
.flag.flag-eg {background-position: -208px -33px}
.flag.flag-eh {background-position: -224px -33px}
.flag.flag-england {background-position: -240px -33px}
.flag.flag-er {background-position: 0 -44px}
.flag.flag-es {background-position: -16px -44px}
.flag.flag-et {background-position: -32px -44px}
.flag.flag-eu {background-position: -48px -44px}
.flag.flag-fi {background-position: -64px -44px}
.flag.flag-fj {background-position: -80px -44px}
.flag.flag-fk {background-position: -96px -44px}
.flag.flag-fm {background-position: -112px -44px}
.flag.flag-fo {background-position: -128px -44px}
.flag.flag-fr {background-position: -144px -44px}
.flag.flag-ga {background-position: -160px -44px}
.flag.flag-gb {background-position: -176px -44px}
.flag.flag-gd {background-position: -192px -44px}
.flag.flag-ge {background-position: -208px -44px}
.flag.flag-gf {background-position: -224px -44px}
.flag.flag-gg {background-position: -240px -44px}
.flag.flag-gh {background-position: 0 -55px}
.flag.flag-gi {background-position: -16px -55px}
.flag.flag-gl {background-position: -32px -55px}
.flag.flag-gm {background-position: -48px -55px}
.flag.flag-gn {background-position: -64px -55px}
.flag.flag-gp {background-position: -80px -55px}
.flag.flag-gq {background-position: -96px -55px}
.flag.flag-gr {background-position: -112px -55px}
.flag.flag-gs {background-position: -128px -55px}
.flag.flag-gt {background-position: -144px -55px}
.flag.flag-gu {background-position: -160px -55px}
.flag.flag-gw {background-position: -176px -55px}
.flag.flag-gy {background-position: -192px -55px}
.flag.flag-hk {background-position: -208px -55px}
.flag.flag-hm {background-position: -224px -55px}
.flag.flag-hn {background-position: -240px -55px}
.flag.flag-hr {background-position: 0 -66px}
.flag.flag-ht {background-position: -16px -66px}
.flag.flag-hu {background-position: -32px -66px}
.flag.flag-ic {background-position: -48px -66px}
.flag.flag-id {background-position: -64px -66px}
.flag.flag-ie {background-position: -80px -66px}
.flag.flag-il {background-position: -96px -66px}
.flag.flag-im {background-position: -112px -66px}
.flag.flag-in {background-position: -128px -66px}
.flag.flag-io {background-position: -144px -66px}
.flag.flag-iq {background-position: -160px -66px}
.flag.flag-ir {background-position: -176px -66px}
.flag.flag-is {background-position: -192px -66px}
.flag.flag-it {background-position: -208px -66px}
.flag.flag-je {background-position: -224px -66px}
.flag.flag-jm {background-position: -240px -66px}
.flag.flag-jo {background-position: 0 -77px}
.flag.flag-jp {background-position: -16px -77px}
.flag.flag-ke {background-position: -32px -77px}
.flag.flag-kg {background-position: -48px -77px}
.flag.flag-kh {background-position: -64px -77px}
.flag.flag-ki {background-position: -80px -77px}
.flag.flag-km {background-position: -96px -77px}
.flag.flag-kn {background-position: -112px -77px}
.flag.flag-kp {background-position: -128px -77px}
.flag.flag-kr {background-position: -144px -77px}
.flag.flag-kurdistan {background-position: -160px -77px}
.flag.flag-kw {background-position: -176px -77px}
.flag.flag-ky {background-position: -192px -77px}
.flag.flag-kz {background-position: -208px -77px}
.flag.flag-la {background-position: -224px -77px}
.flag.flag-lb {background-position: -240px -77px}
.flag.flag-lc {background-position: 0 -88px}
.flag.flag-li {background-position: -16px -88px}
.flag.flag-lk {background-position: -32px -88px}
.flag.flag-lr {background-position: -48px -88px}
.flag.flag-ls {background-position: -64px -88px}
.flag.flag-lt {background-position: -80px -88px}
.flag.flag-lu {background-position: -96px -88px}
.flag.flag-lv {background-position: -112px -88px}
.flag.flag-ly {background-position: -128px -88px}
.flag.flag-ma {background-position: -144px -88px}
.flag.flag-mc {background-position: -160px -88px}
.flag.flag-md {background-position: -176px -88px}
.flag.flag-me {background-position: -192px -88px}
.flag.flag-mg {background-position: -208px -88px}
.flag.flag-mh {background-position: -224px -88px}
.flag.flag-mk {background-position: -240px -88px}
.flag.flag-ml {background-position: 0 -99px}
.flag.flag-mm {background-position: -16px -99px}
.flag.flag-mn {background-position: -32px -99px}
.flag.flag-mo {background-position: -48px -99px}
.flag.flag-mp {background-position: -64px -99px}
.flag.flag-mq {background-position: -80px -99px}
.flag.flag-mr {background-position: -96px -99px}
.flag.flag-ms {background-position: -112px -99px}
.flag.flag-mt {background-position: -128px -99px}
.flag.flag-mu {background-position: -144px -99px}
.flag.flag-mv {background-position: -160px -99px}
.flag.flag-mw {background-position: -176px -99px}
.flag.flag-mx {background-position: -192px -99px}
.flag.flag-my {background-position: -208px -99px}
.flag.flag-mz {background-position: -224px -99px}
.flag.flag-na {background-position: -240px -99px}
.flag.flag-nc {background-position: 0 -110px}
.flag.flag-ne {background-position: -16px -110px}
.flag.flag-nf {background-position: -32px -110px}
.flag.flag-ng {background-position: -48px -110px}
.flag.flag-ni {background-position: -64px -110px}
.flag.flag-nl {background-position: -80px -110px}
.flag.flag-no {background-position: -96px -110px}
.flag.flag-np {background-position: -112px -110px}
.flag.flag-nr {background-position: -128px -110px}
.flag.flag-nu {background-position: -144px -110px}
.flag.flag-nz {background-position: -160px -110px}
.flag.flag-om {background-position: -176px -110px}
.flag.flag-pa {background-position: -192px -110px}
.flag.flag-pe {background-position: -208px -110px}
.flag.flag-pf {background-position: -224px -110px}
.flag.flag-pg {background-position: -240px -110px}
.flag.flag-ph {background-position: 0 -121px}
.flag.flag-pk {background-position: -16px -121px}
.flag.flag-pl {background-position: -32px -121px}
.flag.flag-pm {background-position: -48px -121px}
.flag.flag-pn {background-position: -64px -121px}
.flag.flag-pr {background-position: -80px -121px}
.flag.flag-ps {background-position: -96px -121px}
.flag.flag-pt {background-position: -112px -121px}
.flag.flag-pw {background-position: -128px -121px}
.flag.flag-py {background-position: -144px -121px}
.flag.flag-qa {background-position: -160px -121px}
.flag.flag-re {background-position: -176px -121px}
.flag.flag-ro {background-position: -192px -121px}
.flag.flag-rs {background-position: -208px -121px}
.flag.flag-ru {background-position: -224px -121px}
.flag.flag-rw {background-position: -240px -121px}
.flag.flag-sa {background-position: 0 -132px}
.flag.flag-sb {background-position: -16px -132px}
.flag.flag-sc {background-position: -32px -132px}
.flag.flag-scotland {background-position: -48px -132px}
.flag.flag-sd {background-position: -64px -132px}
.flag.flag-se {background-position: -80px -132px}
.flag.flag-sg {background-position: -96px -132px}
.flag.flag-sh {background-position: -112px -132px}
.flag.flag-si {background-position: -128px -132px}
.flag.flag-sk {background-position: -144px -132px}
.flag.flag-sl {background-position: -160px -132px}
.flag.flag-sm {background-position: -176px -132px}
.flag.flag-sn {background-position: -192px -132px}
.flag.flag-so {background-position: -208px -132px}
.flag.flag-somaliland {background-position: -224px -132px}
.flag.flag-sr {background-position: -240px -132px}
.flag.flag-ss {background-position: 0 -143px}
.flag.flag-st {background-position: -16px -143px}
.flag.flag-sv {background-position: -32px -143px}
.flag.flag-sx {background-position: -48px -143px}
.flag.flag-sy {background-position: -64px -143px}
.flag.flag-sz {background-position: -80px -143px}
.flag.flag-tc {background-position: -96px -143px}
.flag.flag-td {background-position: -112px -143px}
.flag.flag-tf {background-position: -128px -143px}
.flag.flag-tg {background-position: -144px -143px}
.flag.flag-th {background-position: -160px -143px}
.flag.flag-tibet {background-position: -176px -143px}
.flag.flag-tj {background-position: -192px -143px}
.flag.flag-tk {background-position: -208px -143px}
.flag.flag-tl {background-position: -224px -143px}
.flag.flag-tm {background-position: -240px -143px}
.flag.flag-tn {background-position: 0 -154px}
.flag.flag-to {background-position: -16px -154px}
.flag.flag-tr {background-position: -32px -154px}
.flag.flag-tt {background-position: -48px -154px}
.flag.flag-tv {background-position: -64px -154px}
.flag.flag-tw {background-position: -80px -154px}
.flag.flag-tz {background-position: -96px -154px}
.flag.flag-ua {background-position: -112px -154px}
.flag.flag-ug {background-position: -128px -154px}
.flag.flag-um {background-position: -144px -154px}
.flag.flag-us {background-position: -160px -154px}
.flag.flag-uy {background-position: -176px -154px}
.flag.flag-uz {background-position: -192px -154px}
.flag.flag-va {background-position: -208px -154px}
.flag.flag-vc {background-position: -224px -154px}
.flag.flag-ve {background-position: -240px -154px}
.flag.flag-vg {background-position: 0 -165px}
.flag.flag-vi {background-position: -16px -165px}
.flag.flag-vn {background-position: -32px -165px}
.flag.flag-vu {background-position: -48px -165px}
.flag.flag-wales {background-position: -64px -165px}
.flag.flag-wf {background-position: -80px -165px}
.flag.flag-ws {background-position: -96px -165px}
.flag.flag-xk {background-position: -112px -165px}
.flag.flag-ye {background-position: -128px -165px}
.flag.flag-yt {background-position: -144px -165px}
.flag.flag-za {background-position: -160px -165px}
.flag.flag-zanzibar {background-position: -176px -165px}
.flag.flag-zm {background-position: -192px -165px}
.flag.flag-zw {background-position: -208px -165px}

 * Footer
a:link    {color:orangered;  text-decoration:none}
a:visited {color:orangered; text-decoration:none}
a:hover   {color:red; text-decoration:underline}

  margin-top: 15px;
  width: 32px;
              // Define the dimensions of the visualization. 
// We're using a size that's convenient for displaying the graphic on
var margin  = {top: 10, right: 5, bottom: 10, left: 100},
    width   = 1400-margin.left-margin.right,
    height  = 900-margin.top-margin.bottom;   
//We start off by creating an SVG
// container to hold the visualization. We only need to specify
// the dimensions for this container.
var svg = d3.select("body").append("svg")

//create the tooltip that holds the country name
var tooltip = d3.select('body').append('div') .attr("class","tooltip")
        'background' : 'orangered',

  // Extract the nodes and links from the data.
  var nodes = data["nodes"];
  var links = data["links"];
  // Now we create a force layout object and define its properties.
  // Those include the dimensions of the visualization and the arrays
  // of nodes and links.
  var force = d3.layout.force()
// There's one more property of the layout we need to define,
// its `linkDistance`. That's generally a configurable value and,
// for a simple example, we'd normally leave it at its default.
// Unfortunately, the default value results in a visualization
// that's not especially clear. This parameter defines the
// distance (normally in pixels) that we'd like to have between
// nodes that are connected. (It is, thus, the length we'd
// like our links to have.)
//now so it's time to turn
// things over to the force layout. Here we go.
// Next we'll add the nodes and links to the visualization.
// Note that we're just sticking them into the SVG container
// at this point. We start with the links. The order here is
// important because we want the nodes to appear "on top of"
// the links. SVG doesn't really have a convenient equivalent
// to HTML's `z-index`; instead it relies on the order of the
// elements in the markup. By adding the nodes _after_ the
// links we ensure that nodes appear on top of links.

// Links are pretty simple. They're just SVG lines, and
// we're not even going to specify their coordinates. (We'll
// let the force layout take care of that.) Without any
// coordinates, the lines won't even be visible, but the
// markup will be sitting inside the SVG container ready
// and waiting for the force layout.
  var link = svg.selectAll('.link')
  // Now it's the nodes turn. Each node is drawn as a flag.
  var node = d3.select('#flags').selectAll('img')
  //we return the exact flag of each country from the image
    .attr('class', function (d) { return 'flag flag-' + d.code; })
  //we call some classes to handle the mouse
    .on('mouseover', mouseoverHandler)
    .on("mouseout", mouseoutHandler);
  // We're about to tell the force layout to start its
  // calculations. We do, however, want to know when those
  // calculations are complete, so before we kick things off
  // we'll define a function that we want the layout to call
  // once the calculations are done.
  function tick(e){
    // First let's reposition the nodes. As the force
    // layout runs it updates the `x` and `y` properties
    // that define where the node should be positioned.
    // To move the node, we set the appropriate SVG
    // attributes to their new values. 
     node.style('left', function (d) { return d.x + 'px'; })
         .style('top', function (d) { return d.y + 'px'; })
    // We also need to update positions of the links.
    // For those elements, the force layout sets the
    // `source` and `target` properties, specifying
    // `x` and `y` values in each case.
    link.attr('x1', function(d){ return  d.source.x})
        .attr('y1',function(d){ return  d.source.y})
        .attr('x2', function(d){ return  d.target.x})
        .attr('y2',function(d){ return   d.target.y})
  //hover over a flag
  //the tooltip with the name of the country is going to show up
  function mouseoverHandler (d) {
     tooltip.transition().style('opacity', .9)
     tooltip.html('<p>' + d["country"] + '</p>' );
  //leaving a flag
  //the tooltip will disappear
  function mouseoutHandler (d) {
      tooltip.transition().style('opacity', 0);

  function mouseMoving (d) {
      tooltip.style("top", (d3.event.pageY-10)+"px").style("left",(d3.event.pageX+10)+"px").style("color","white");
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