var n=-1;
var arrimg = ['','','','',''];
var arrhref = ['','','','',''];

function slide(i) {
    arrimg[0] = document.getElementById("sliderimg1").src;
    arrimg[1] = document.getElementById("sliderimg2").src;
        arrimg[2] = document.getElementById("sliderimg3").src;
    arrimg[3] = document.getElementById("sliderimg4").src;
        arrimg[4] = document.getElementById("sliderimg5").src;
    arrhref[0] = document.getElementById("slidera1").href;
    arrhref[1] = document.getElementById("slidera2").href;
        arrhref[2] = document.getElementById("slidera3").href;
    arrhref[3] = document.getElementById("slidera4").href;
        arrhref[4] = document.getElementById("slidera5").href;
    n=n+i;
        if (n==-1) {n=4};
        if (n==5) {n=0};
    document.getElementById("sliderimg").src=arrimg[n];
        document.getElementById("slidera").href=arrhref[n];
};

window.setInterval("slide(1);", 5000);