function go_to_next_question(question){
        var value='';
        var ok=true;
        if(question==1){
            var name=document.getElementById('user_name').value;
            var surname=document.getElementById('surname').value;
            var day=document.getElementById('select-1').value;
            var mons=document.getElementById('select-2').value;
            var year=document.getElementById('select-3').value;
            var male=document.getElementById('male').checked;
            var sex='';
            if(male==true){
                sex='м';
            }else{
                var female=document.getElementById('female').checked;
                if(female==true){
                    sex='ж';
                }
            }
            var birthday=year+'-'+mons+'-'+day;
            save_user(name,surname,birthday,sex);
        }
            if(question!=1 && question!=2){
             var editbox=document.getElementById('answer0');
             var i=1;
             ok=false;
             while(editbox){
                if(editbox.checked){
                    ok=true;
                }
                editbox=document.getElementById('answer'+i);
                i++;
             }
             if(!ok)
           		 document.getElementById('error').innerHTML='Выберите один из вариантов.';
          }

        if(ok==true){
            load_next_question(question,value);
        }    
    }
    
    function load_next_question(question,value){
	       URL = "change_question.php?"+"question="+question+value;;
	       request=open_XMLHttpRequest();
	       if (request){
		      request.onreadystatechange = processStateChange;
		      request.open("GET", URL, true);
		      request.send(null);
	       }   
    }
    
    function go_to_next_page(page){
	    if(page=='3'){
	        top.location.href="/result.php";
	      }else
	      {
	    URL = "change_content.php?"+"page="+page;
	    request=open_XMLHttpRequest();
	    if (request){
	      if(page=='1'){
	        request.onreadystatechange = processStateChange_page2;
	      }else  request.onreadystatechange = processStateChange;
		  request.open("GET", URL, true);
		  request.send(null);
	   }
	      }
    }
    
     function save_user(name,surname,birthday,sex){
	    URL = "save_user.php";
	    request=open_XMLHttpRequest();
	    if (request){
		  request.onreadystatechange = processStateChange_save_user;
		  request.open("POST", URL, true);
		  request.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
          var param="name="+name+"&surname="+surname+"&birthday="+birthday+"&sex="+sex;
		  request.send(param);
	   }
    }

    function processStateChange_page2(){
	  if (request.readyState < 4) document.getElementById('content_bg').innerHTML = "Загрузка...";
    	if (request.readyState == 4){
		  if (request.status == 200){
			document.getElementById('content_bg').innerHTML = request.responseText;
            document.getElementById('user_name').focus();
		  }else{
			document.getElementById('content_bg').innerHTML = "Error: Status "+request.status;
		}
	   }
    }
    
    function processStateChange(){
	   if (request.readyState < 4) document.getElementById('content_bg').innerHTML = "Загрузка...";
    	if (request.readyState == 4){
		  if (request.status == 200){
			document.getElementById('content_bg').innerHTML = request.responseText;
			$('#select-4').selectbox();
		  }else{
			document.getElementById('content_bg').innerHTML = "Error: Status "+request.status;
		}
	   }
    }
    function processStateChange_save_user(){

    }
    
    function select_box(id){
        if(document.getElementById(id).className=='box_sel'){
           document.getElementById(id).className='box';
        }else 
            document.getElementById(id).className='box_sel';
    }

    function open_XMLHttpRequest(){
	   if (window.XMLHttpRequest){
	      request = new XMLHttpRequest();
	   }else if (window.ActiveXObject) {
			     request = new ActiveXObject("Microsoft.XMLHTTP");
             }
	   return request;
    }
    
    function set_GetElementsByClassName(){
        document.getElementsByClassName = function(str) {
        var list = new Array();
        var nodes = document.getElementsByTagName('*')
        for (i = 0; i<nodes.length; i++){
            if (nodes[i].className.indexOf(str) >= 0){
                list.push(nodes[i]);
            }
        }
        return list;
        }
    }
    
    function get_counters(){
       	URL = "statistic.php";
	    request=open_XMLHttpRequest();
	    if (request){
		  request.onreadystatechange = processStateChange_counters;
		  request.open("POST", URL, true);
		  request.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
		  request.send();
	   }
    }
    
    function processStateChange_counters(){
	   if (request.readyState < 4) document.getElementById('counters').innerHTML = "Загрузка...";
    	if (request.readyState == 4){
		  if (request.status == 200){
			document.getElementById('counters').innerHTML = request.responseText;
		  }else{
			document.getElementById('counters').innerHTML = "Error: Status "+request.status;
		}
	   }
    }
    
    function get_result(){
        URL = "check_sms_code.php";
        var code=document.getElementById('input_sms_code').value;
        if(code==''){
            document.getElementById('error').innerHTML='Вы не ввели код.';
        }else{
            request=open_XMLHttpRequest();
	        if (request){
               request.onreadystatechange = processStateChange_check_code;
		       request.open("POST", URL, true);
               request.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
               var param="code="+code;
		       request.send(param);
	       }
        }
    }
    
     function processStateChange_check_code(){
	   if (request.readyState < 4) document.getElementById('error').innerHTML = "Загрузка...";
    	if (request.readyState == 4){
		  if (request.status == 200){
			document.getElementById('error').innerHTML = request.responseText;
		  }else{
			document.getElementById('error').innerHTML = "Error: Status "+request.status;
		}
	   }
    }
          
        function check_num(str,valid_chars){
            valid_string=true;
            if(str.length==0) return false;
             for(i=0; i < str.length; i++ ){
               current_valid_char = false;
                for(j=0; j < valid_chars.length; j++){
                    if(str.charAt(i) == valid_chars.charAt(j)){
                        current_valid_char = true;
                    }
                }
                if(current_valid_char == false){
                    valid_string = false;
                } 
            }
            return valid_string; 
        }
        
    function change_country(){
       var country=document.getElementById('select-4').value;
       if(country=="Россия"){
          country=0;
       }else{
            if(country=="Украина"){
                country=1;
            }
       }
        URL = "change_country.php";
            request=open_XMLHttpRequest();
	        if (request){
               request.onreadystatechange = processStateChange_change_country;
		       request.open("POST", URL, true);
               request.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
               var param="country="+country;
		       request.send(param);
	       }
        }
        
     function processStateChange_change_country(){
	   if (request.readyState < 4) document.getElementById('sms_message').innerHTML = "Загрузка...";
    	if (request.readyState == 4){
		  if (request.status == 200){
			document.getElementById('sms_message').innerHTML = request.responseText;
		  }else{
			document.getElementById('sms_message').innerHTML = "Error: Status "+request.status;
		}
	   }
    } 
    
    function send_comment(){
       var user_name=document.getElementById('user_name').value;
       var text_comment=document.getElementById('text_comment').value;
        var ok=true;
       if(user_name==''){
            document.getElementById('error1').innerHTML='Введите пожалуйста ваше имя.';
            ok=false;
       }
       if(text_comment==''){
            document.getElementById('error1').innerHTML='Введите пожалуйста текст комментария.';
            ok=false;
       }  
       if(ok){    
	    URL = "send_comment.php";
	    request=open_XMLHttpRequest();
	    if (request){
          request.onreadystatechange = processStateChange_send_comment;
		  request.open("POST", URL, true);
		  request.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
          var param="user_name="+user_name+"&text_comment="+text_comment;
		  request.send(param);
	   }
      }  
    }
      function processStateChange_send_comment(){
	   if (request.readyState < 4) document.getElementById('comment').innerHTML = "Загрузка...";
    	if (request.readyState == 4){
		  if (request.status == 200){
			document.getElementById('comment').innerHTML = request.responseText;
		  }else{
			document.getElementById('comment').innerHTML = "Error: Status "+request.status;
		}
	   }
    } 
    function select_radio(x){
		document.getElementById('answer'+x).checked=1;
	}