Should I make a proxy generator?

Question

JavaScript

I was looking for free proxies, added about 20 sites from which I took them, in general, about 20,000 proxies were collected per day, of which 4000-5000 were working.
Further, while collecting data from other resources, I found that they are repeated, not surprising of course ...
And then I decided to think about making a bicycle - to fill the database with randomly created ip and then sort through (check) them through my own server, that is, send a curl request to my the same server and, depending on the response, mark as not working or debug as working.
Considering that there are 3 ports I need (80, 8080, 3128), they are mainly used (although of course there may be others), then according to my calculations, it will take about a month to process (about 13 billion combinations), checking with a multi-request for 1000 pieces in 3- 4sec.
The questions are:
Is it worth trying to collect them?
Proxies can work now and not work after 5 seconds, if just at that time there is a check, it will indicate that it is not working.
How many can there be?
If there are about 100 thousand of them, then the probability is very small then to collect them, on the other hand, if there are millions of them, then of course the chance increases.
Where do other services get them?
Well, they can’t just tear them apart from each other, somewhere there is a source from where at least some services find them ...

Answer 1

Try like this.

<a href="#" class="parent">first</a> <div class="child" style="display:none"><ul><li>один</li><li>два</li><li>три</li></ul></div>
<a href="#" class="parent">second</a> <div class="child" style="display:none"><ul><li>один</li><li>два</li><li>три</li></ul></div>
<a href="#" class="parent">third</a> <div class="child" style="display:none"><ul><li>один</li><li>два</li><li>три</li></ul>

$(".parent").on("click",function(){
  $(this).next(".child").attr("style","display:inline;position: absolute")
})
$(".parent").mouseout(function(){
$(this).next(".child").attr("style","display:none");
})

Answer 2

The maximum you can draw " live " a couple of tens of thousands.
Public ones do not live long, you will have to constantly (with a short time interval) check
because There are hundreds of proxy sources, and hundreds of verified IPs. thousand, this task is not an easy one - it will take resources and a loyal provider (ignoring many connections)
example