database=new Array("truck_alg.html","truck_alg2.html","truck_bouw.html","truck_bouw2.html","truck_bouw3.html","truck_brand.html","truck_brand2.html","truck_bus.html","truck_bus2.html","truck_bus3.html","truckl_D.html","truckl_D2.html","truckl_DDR.html","truckl_F.html","truckl_USA.html","truckm_Autocar.html","truckm_Bedfordrep.html","truckm_Berliet.html","truckm_Bernard.html","truckm_Citroen.html","truckm_DAFrep.html","truckm_DiamondT.html","truckm_Dodge.html","truckm_Faun.html","truckm_Federal.html","truckm_FordUSA.html","truckm_GMC.html","truckm_Hanomag.html","truckm_Henschel.html","truckm_Hotchkiss.html","truckm_Ivecorep.html","truckm_Ivecorep2.html","truckm_Kenworth.html","truckm_Krupp.html","truckm_MAN.html","truckm_MANrep.html","truckm_MercedesBenz.html","truckm_MercedesBenzrep.html","truckm_MercedesBenzrep2.html","truckm_Mitsubishirep.html","truckm_Nissanrep.html","truckm_Opel.html","truckm_Peterbilt.html","truckm_Renaultrep.html","truckm_Renaultrep2.html","truckm_Saviem.html","truckm_Scania.html","truckm_Scaniarep.html","truckm_Sterling.html","truckm_Stevens.html","truckm_Unimog.html","truckm_Volvorep.html","truckm_White.html","truckm_Willeme.html");

NumberOfFiles=database.length;
StringA=window.location.href;
LengthA=StringA.length;
A=StringA.lastIndexOf("/")+1;
ThisFilename=StringA.substring(A,LengthA);
n=NumberOfFiles-1;

for (var z=0;z<=n;z++)
{
if (database[z]==ThisFilename)
{
ThisPageNumber=z;
}
}
function goBack(){
if (ThisPageNumber-1<0)
{
alert("You are at the beginning of the series");
}
else
{window.location=database[ThisPageNumber-1];
}
}
function goForward(){
if (ThisPageNumber+1>n)
{
alert("You are at the end of the series");
}
else
{window.location=database[ThisPageNumber+1];}}