var photo=new Array()
var num=0
photo[0]="images/poca01.jpg"
photo[1]="images/poca02.jpg"
photo[2]="images/poca03.jpg"
photo[3]="images/poca04.jpg"
photo[4]="images/poca05.jpg"
photo[5]="images/poca06.jpg"
photo[6]="images/poca07.jpg"
photo[7]="images/poca08.jpg"
photo[8]="images/poca09.jpg"
photo[9]="images/poca10.jpg"
photo[10]="images/poca11.jpg"
photo[11]="images/poca12.jpg"
photo[12]="images/poca13.jpg"
photo[13]="images/poca14.jpg"
photo[14]="images/poca15.jpg"
photo[15]="images/poca16.jpg"
photo[16]="images/poca17.jpg"
photo[17]="images/poca18.jpg"
photo[18]="images/poca19.jpg"
photo[19]="images/poca20.jpg"
photo[20]="images/poca21.jpg"
photo[21]="images/poca22.jpg"
photo[22]="images/poca23.jpg"
photo[23]="images/poca24.jpg"
numero=num+1

function precedente() {
  if (num>0) {
    num--
      document.image.src=photo[num];
    numero=num+1
  }
}
function suivante() {
  if(num<photo.length-1) {
    num++
      document.image.src=photo[num];
    numero=num+1
  }
}