<form action="form_gcm.html" method="get">
  DATA-1: <input type="text" name="data1">
  DATA-2: <input type="text" name="data2">
  <input type="submit">
</form>

<script type="text/javascript">
    param = new Array();
    //window.alert(window.location.search);
    if (window.location.search.length>12)
    {   var query = window.location.search.substring(1);
        var parameters = query.split('&');
        for(i=0; i<parameters.length; i++)
        {
            var element = parameters[i].split('=');
            var paramName = decodeURIComponent(element[0]);
            var paramValue = decodeURIComponent(element[1]);
            param[paramName] = parseInt(paramValue);
        }
        document.write('<p><hr></p>');
        d1 = param["data1"];
        d2 = param["data2"];
        document.write(d1, " : ", d2, "<br>");
        while(d1!=d2)
        {   if (d1>d2)  d1 = d1 - d2;
            else        d2 = d2 - d1;
        }
        document.write("GCM : ", d1, "<br>");
    }
</script>

<form action="form_gcm.html" method="get">
  DATA-1: <input type="text" name="data1">
  DATA-2: <input type="text" name="data2">
  <input type="submit">
</form>

    param = new Array();
    if (window.location.search.length>12)
    {   var query = window.location.search.substring(1);
        var parameters = query.split('&');
        for(i=0; i<parameters.length; i++)
        {
            var element = parameters[i].split('=');
            var paramName = decodeURIComponent(element[0]);
            var paramValue = decodeURIComponent(element[1]);
            param[paramName] = parseInt(paramValue);
        }
        document.write('<p><img src="img/bar_gh.gif"></p>');
        d1 = param["data1"];
        d2 = param["data2"];
        document.write(d1, " : ", d2, "<br>");
        while(d1!=d2)
        {   if (d1>d2)  d1 = d1 - d2;
            else        d2 = d2 - d1;
        }
        document.write("GCM : ", d1, "<br>");
    }