function showhide1(str1, str2, str3) {
	element1 = document.getElementById(str1);
	element2 = document.getElementById(str2);
	element3 = document.getElementById(str3);
	
	element1.style.display = 'block';
	element2.style.display = 'none';
	element3.style.display = 'none';
}

function showhide2(str1, str2, str3) {
	element1 = document.getElementById(str1);
	element2 = document.getElementById(str2);
	element3 = document.getElementById(str3);
	
	element1.style.display = 'block';
	element2.style.display = 'none';
	element3.style.display = 'none';
}

function screenshot(str) {
	var i = document.form1.selected.selectedIndex;
	var l = document.form1.selected.length;
	l = l - 1;
	if (!document.images)
	return
	for(x=0; x<=l; x++) {
		document.getElementById("index"+x).style.display = 'none';		
	}
	document.getElementById("index"+str).style.display = 'block';
	document.form2.img.src = document.form1.selected.options[i].value
	if(i > 0) {
		document.getElementById('previous').style.display = 'block';
	} else {
		document.getElementById('previous').style.display = 'none';		
	}
	if(i == l) {
		document.getElementById('next').style.display = 'none';
	} else {
		document.getElementById('next').style.display = 'block';		
	}
}

function prev() {
	var i = document.form1.selected.selectedIndex;
	var l = document.form1.selected.length;
	var id = document.getElementById('previous');
	i = i - 1;
	document.form1.selected.selectedIndex = i;
	screenshot(i);	
	document.form2.img.src = document.form1.selected.options[i].value;
		document.getElementById('next').style.display = 'block';
	//alert(i);
	if(i == 0) {
		i = i + 2;
		id.style.display = 'none';
	}
}

function next() {
	var l = document.form1.selected.length;
	var i = document.form1.selected.selectedIndex;
	var id = document.getElementById('next');
	i = i + 1;
	l = l - 1;
	document.form1.selected.selectedIndex = i;	
	screenshot(i);	
	document.form2.img.src = document.form1.selected.options[i].value;
		document.getElementById('previous').style.display = 'block';
	//alert(l);
	if(i == l) {
		id.style.display = 'none';
	}
}