function showtab(id){
	names = new Array ("tabname_1","tabname_2");
	conts= new Array ("tabcontent_1","tabcontent_2");
	for(i=0;i<names.length;i++) {
	 document.getElementById(names[i]).className = 'nonactive';
	 }
	for(i=0;i<conts.length;i++) {
	 document.getElementById(conts[i]).className = 'hide';
	 }
	document.getElementById('tabname_' + id).className = 'active';
	document.getElementById('tabcontent_' + id).className = 'show';
}