if(document.layers)var n4 = true;
if(document.all)var ie = true;
if(document.getElementById)var n6 = true;

function picCh(x)
	{
    var pics = new Array('p1','p2','p3','p4','p5','p6','p7','p8','p9','p10','p11','p12');
    for(i=0;i<pics.length;i++) {
			 {
					if(n6 || ie) {
						
						if (document.getElementById(pics[i])) { // alert(pics[i]);
							document.getElementById(pics[i]).style.visibility = "hidden";
						}
					}
					if(n4)  {
						if (document.layers[pics[i]]) {
							document.layers[pics[i]].visibility = "hidden";
						}
					}
					
			}
    }
	
    if(n6 || ie) {
                document.getElementById(x).style.visibility = "visible";
				}
	if(n4)  {
                document.layers[x].visibility = "show"; 
				}			
  }