Cyclability in jquery

[meriah]

There are three blocks with the class item. How to add a class every 3 seconds. active to the next element?

I do it, but it doesn't work.

$(function() {
    $(document).each(function() {
        $(".item").removeClass("active");
        $(".item.active").next().addClass("active");
    });
});

[Trenton]

Try this:

var params = {
  count: $(".item").length,
  now: 0
}
function set_active() {

if(params.now == params.count) {

params.now = 0;

}
$(".item").removeClass("active");

$(".item[data-id="" + params.now + ""]").addClass("active");
params.now++;

}
set_active();
setInterval(set_active, 3000);

.active {

color: red;

}

<script src="//code.jquery.com/jquery.min.js"></script>

<div class="item" data-id="0">Привет</div>

<div class="item" data-id="1">Привет</div>

<div class="item" data-id="2">Привет</div>