arrfotor=[["top_1.jpg","1"],["top_1_2.jpg","2"],["top_1_3.jpg","3"]];
var pos = parseInt(Math.random()*arrfotor.length);
ffoto = arrfotor[pos][0];
idfoto = arrfotor[pos][1];
document.write("<img border=\"0\" src=\"images/"+ffoto+"\" width=\"956\" height=\"165\" alt=\"compraventa.zarrapas\"></a>");