function showImage(containerId, index)
{
    var container = document.getElementById(containerId);
    var nodes = container.getElementsByTagName("img");
    
    for (var i = 0; i < nodes.length; i++)
    {
        var node = nodes[i];
        node.style.display = "none";
    }
    
    if (nodes[index]) nodes[index].style.display = "block";
}