function showDiv(nameDiv,pocet_prvku,actual){
    if(nameDiv != 'other') var actual_id = "#"+nameDiv+"_"+actual;

    if(nameDiv == 'vip') {
        showRandom(nameDiv,pocet_prvku,actual_id);
    }
    if(nameDiv == 'imp') {
        showRandom(nameDiv,pocet_prvku,actual_id);
    }
    if(nameDiv == 'other'){
        for(i=0;i<actual.length;i++){
            var actual_div = "#"+nameDiv+"_"+actual[i];
            $(actual_div).hide();
        }
        var new_actual = new Array();
        while(new_actual.length != 3){
            ranNum = randNum(pocet_prvku);
            if(!inArray(ranNum,new_actual)){
                var toShow = "#"+nameDiv+"_"+ranNum;
                new_actual.push(ranNum);
                $(toShow).show();
            }
        }
    } 
}

/*
* return nahodne cislo v intervalu 1 az num
*/
function randNum (num) {
    var rand = Math.round( (num-1) * Math.random() + 1 )
    return rand;
}

function showRandom(nameDiv,pocet_prvku,actual_id){
    $(actual_id).hide();
    var new_actual = "#"+nameDiv+"_"+randNum(pocet_prvku);
    $(new_actual).show();
}

function inArray(numFind,arr){
    if (arr.length > 0) {
        for(i=0;i<arr.length;i++){
            if(numFind == arr[i]) return true;
        }
    }
    return false;
}