var GetRandomn = 1;
function GetRandom(n){GetRandomn=Math.floor(Math.random()*n+1)}
GetRandom("3");
switch(GetRandomn){
case 1:
document.write('
')
break;
case 2:
document.write('
')
break;
case 3:
document.write('
')
break;
case 4:
document.write('
')
break;
}