function calculator() 
{
if (form.numberpr!=null && form.numberpr.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !=""
  || form.numberpr1!=null && form.numberpr1.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !="" 
  || form.numberpr1!=null && form.numberpr1.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !=""
  || form.numbermd!=null && form.numbermd.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !=""
  || form.numbermd!=null && form.numbermd.selectedIndex!=0 && form.numberpr1!=null && form.numberpr1.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !=""
  || form.numberpr1!=null && form.numberpr1.selectedIndex!=0 && form.numberpr!=null && form.numberpr.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !=""
  || form.numbermd!=null && form.numbermd.selectedIndex!=0 && form.numberpr1!=null && form.numberpr1.selectedIndex!=0 && form.numberpr!=null && form.numberpr.selectedIndex!=0 &&
form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !=""
  || form.numberpr1==null && form.numbermd!=null && form.numbermd.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !=""
  || form.numberpr1==null && form.numberpr!=null && form.numberpr.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !=""
  || form.numberpr1==null && form.numberpr!=null && form.numberpr.selectedIndex!=0 && form.numbermd!=null && form.numbermd.selectedIndex!=0 && form.numbernights!=null && form.numbernights.selectedIndex!=0 && form.ADate!=null && form.ADate.value !="")
{
form.sub.disabled=false;
document.getElementById('warning').style.display='none'
}
else
{
form.sub.disabled=true;
form.sub.enabled=false;
document.getElementById('warning').style.display='block'
}
dr = eval(form.dollar.value);
er = eval(form.euro.value);
if (form.number10==null && form.numberpr==null && form.numbermd==null && form.numbernights==null && form.ADate==null) {
bi = document.form.number;
for (i=0; i< bi.length; i++) {
  if (bi[i].checked) {
bx = bi[i].value;
	 break;
	 }
     }
}


if (form.gbgdnumber!=null) {
kbi = document.form.gbgdnumber;
for (j=0; j< kbi.length; j++) {
  if (kbi[j].checked) {
kbx = kbi[j].value;
	 break;
	 }
     }
}
if (form.number10==null && form.numberpr==null && form.numbermd==null && form.numbernights==null && form.ADate==null && form.gbgdnumber==null && bx==1) {
b1 = eval(form.basic1.value);
b = b1;
}
else if(form.number10==null && form.numberpr==null && form.numbermd==null && form.numbernights==null && form.ADate==null && form.gbgdnumber==null && bx==2) {
b2 = eval(form.basic2.value);
b = b2;
}
else if (form.number10==null && form.numberpr==null && form.numbermd==null && form.numbernights==null && form.ADate==null && form.gbgdnumber!=null && kbx==1 && bx==1) {
b3 = eval(form.basic1.value);
b = b3;
}
else if(form.number10==null && form.numberpr==null && form.numbermd==null && form.numbernights==null && form.ADate==null && form.gbgdnumber!=null && kbx==1 && bx==2) {
b4 = eval(form.basic2.value);
b = b4;
}
else if(form.number10==null && form.numberpr==null && form.numbermd==null && form.numbernights==null && form.ADate==null && form.gbgdnumber!=null && kbx==2 && bx==1) {
b5 = eval(form.basic1of2.value);
b = b5;
}
else if(form.number10==null && form.numberpr==null && form.numbermd==null && form.numbernights==null && form.ADate==null && form.gbgdnumber!=null && kbx==2 && bx==2) {
b6 = eval(form.basic2of2.value);
b = b6;
}
else
{
b=0;
}
if(form.extra_vill!=null && form.extra_vill.checked == true && bx==1){
v1 = eval(form.extra_vil1.value);
v=v1;
}
else if(form.extra_vill!=null && form.extra_vill.checked == true && bx==2){
v2 = eval(form.extra_vil2.value);
v=v2;
}
else
{
v=0;
}
if(form.extra_irk!=null && form.extra_irk.checked == true && bx==1){
i1 = eval(form.extra_irk1.value);
ir=i1;
}
else if(form.extra_irk!=null && form.extra_irk.checked == true && bx==2){
i2 = eval(form.extra_irk2.value);
ir=i2;
}
else
{
ir=0;
}
if (form.number10!=null){
var dd = form.number10.selectedIndex;
var n10 = form.number10[dd].text;
bas = eval(form.basic1.value);
n10 = eval(n10);
if (form.number10.selectedIndex!=0){
n=bas*n10;
}
else
{
n=0;
}
}
else
{
n=0;
}
if (form.numberpr!=null && form.numberpr1!=null && form.numbermd!=null && form.numbernights!=null){
var prenp1 = form.numberpr1.selectedIndex;
npr1 = eval(prenp1);
prp1 = eval(form.private1cost.value);
pr1=prp1*npr1;
var prenp = form.numberpr.selectedIndex;
npr = eval(prenp);
prp = eval(form.privatecost.value);
pr=prp*npr;
var prenm = form.numbermd.selectedIndex;
nm = eval(prenm);
mxp = eval(form.mixdormcost.value);
mx=mxp*nm;
var prenn = form.numbernights.selectedIndex;
nn = eval(prenn);
s1=(pr1+pr+mx)*nn;
}
else
{
s1=0;
}
if (form.numberpr!=null && form.numbermd!=null && form.numbernights!=null && form.numberpr1==null){
var prenp = form.numberpr.selectedIndex;
npr = eval(prenp);
prp = eval(form.privatecost.value);
pr=prp*npr;
var prenm = form.numbermd.selectedIndex;
nm = eval(prenm);
mxp = eval(form.mixdormcost.value);
mx=mxp*nm;
var prenn = form.numbernights.selectedIndex;
nn = eval(prenn);
s=(pr+mx)*nn;
}
else
{
s=0;
}
prer=b+v+ir+n+s+s1;
r= eval(prer);
dl=r/dr;
d=(dl).toFixed(0);
el=r/er;
e=(el).toFixed(0);
if (r!=0 && form.language==null || r!=0 && form.language!=null && form.language.value=="en"){
var obj = document.getElementById('total');
obj.innerHTML = r+" "+"rub."+" "+"or"+" "+"$"+d+" "+"or"+" "+"ˆ"+e; 
form.sub.disabled=false;
document.getElementById('warning').style.display='none' 
}
else if (r!=0 && form.language!=null && form.language.value=="ru"){
var obj = document.getElementById('total');
obj.innerHTML = r+" "+"ðóá.";
form.sub.disabled=false;
document.getElementById('warning').style.display='none'
}
else if (r!=0 && form.language!=null && form.language.value=="de"){
var obj = document.getElementById('total');
obj.innerHTML = r+" "+"Rub."+" "+"oder"+" "+"$"+d+" "+"oder"+" "+"ˆ"+e; 
form.sub.disabled=false;
document.getElementById('warning').style.display='none'
}
else 
{
obj.innerHTML = "";
form.sub.disabled=true;
document.getElementById('warning').style.display='block'
}
}