function swapIt(element,swaptext)
{
    var ext=element.src.substr(element.src.length-4,4);
    var source=element.src.substring(0,element.src.length-4);
    source=source.substr(0,source.length-2);
    source+=swaptext;
    element.src=source+ext;
}

function swap0(element)
{
    swapIt(element,"_0");
}

function swap1(element)
{
    swapIt(element,"_1");
}