/*function rozwin(x2){
        if(x2==x1){
            x4=x3;x3=1-x3
        }else if (x1!=0){
            x3=1;x4=1
        }
        
        if(x4==1)D.getElementById('a'+x1).style.display='none';

        if(x3==1)D.getElementById('a'+x2).style.display='block';
        x1=x2;
    }
*/

/* author: Adam Boc adamboc@gmail.com */
var prev_el = 0;
function unfold(el) {
/* el - id elementu */
    if (el != prev_el){
        if (obj = document.getElementById('a'+el)) {
            obj.style.display = 'block';
            if (prev_obj = document.getElementById('a'+prev_el)) {
                prev_obj.style.display = 'none';
            }
    
            prev_el = el;
        }
    }
}