var theImages = new Array()
theImages[0] = '0.jpg'
theImages[1] = '1.jpg'
theImages[2] = '2.jpg'
theImages[3] = '3.jpg'
theImages[4] = '4.jpg'
theImages[6] = '6.jpg'
theImages[7] = '7.jpg'
theImages[8] = '8.jpg'
theImages[9] = '9aa.jpg'
theImages[10] = '10.jpg'
theImages[11] = '11.jpg'
theImages[12] = '12.jpg'

var j = 0
var p = theImages.length;
var preBuffer = new Array()
for (i = 0; i < p; i++){
   preBuffer[i] = new Image()
   preBuffer[i].src = theImages[i]
}
var whichImage = Math.round(Math.random()*(p-1));
function showImage(){
document.write('<img src="http://www.caritas.diecezja.tarnow.pl/img/pict_main/'+theImages[whichImage]+'">');
}