function showDiv(a){q=1;b='div'+q;while(g(b)){H(b);q++;b='div'+q;}S('div'+a);}
function g(i){return document.getElementById(i);}
function H(i){g(i).style.visibility="hidden";g(i).style.display="none";}
function S(i){g(i).style.visibility="visible";g(i).style.display="block";}