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<html>
<head>
<title>Force-Directed Layout</title>
<script type="text/javascript" src="https://d3js.org/d3.v3.min.js" charset="utf-8"></script>
<link type="text/css" rel="stylesheet" href="force.css"/>
</head>
<body>
<div id="chart"></div>
<script type="text/javascript" src="forcec.js"></script>
</body>
</html>
Modified http://d3js.org/d3.v3.min.js to a secure url
https://d3js.org/d3.v3.min.js