optimization – Min number of register without spilling

The program below uses six temporary variables a, b, c, d, e, f.

a = 1
b = 10
c = 20
d = a+b
e = c+d
f = c+e
b = c+e
e = b+f
d = 5+e
return d+f

Assuming that all operations take their operands from registers, what is the minimum number of registers needed to execute this program without spilling?
(A) 2
(B) 3
(C) 4
(D) 6

My attempt :

enter image description here

But, people are using register R3 for variable C.

I’ve applied register re-usability without spilling, so answer is only 2.

My question is :

Whether, can we apply register re-usability or not !?

Register new business

Hello Guys,
I have been working in a Digital Agency for 2 years, Due to the current pandemic situation across the globe, I am working from home
and now, I was thinking of changing my pace in my career and decided to set up an own office business for a digital agency in my hometown, I searched online on how to register a new business online and came across a couple of registrations of websites. Every website has different procedures, and it is very much confusing. I would really appreciate it if anybody could help me by advising me on the above.

Waiting for your positive reply
Thank You.


How can I register for the Debian User Forumns?

When I tried to register for Debian User Forumns I received the following list of error messages:

Your IP <ip> has been blocked because it is blacklisted. For details please see http://www.spamcannibal.org/cannibal.cgi?page=lookup&lookup=<ip>.
Your IP <ip> has been blocked because it is blacklisted. For details please see http://cbl.abuseat.org/lookup.cgi?.submit=Lookup&ip=<ip>.
An entry on the blacklist may have several reasons:
1. You are a well-known spammer.
2. Last time a well-known spammer was using the dynamic IP address which you got from your ISP (Internet Service Provider), your e-mail address or the username you have choosen.
3. Your ISP is well-known for a lot of spamming customers and is not fighting against spammers enough.
Please note that you will need to enter a valid e-mail address before your account is activated. You will receive an e-mail at the address you provide that contains an account activation link.

I visited both links for details and both links were broken. I can’t use this operating system if I can’t access support. But there are no options to contact. Is there anything I can do or is it just broken?

automata – Why do register machines outperform stack machines?

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mac os x – Cannot register python installed via pyenv

I had installed Python3.9.1 via pyenv and installed pyzmp according to the tutorial. But Mathematica can only detect the system Python2.7.



I also try to use RegisterExternalEvaluator function as follows:

RegisterExternalEvaluator["Python", "~/.pyenv/versions/3.9.1/bin/python"]
RegisterExternalEvaluator["Python", "~/.pyenv/shims/python"]

However Mathematica returns me


But I did have pyzmp installed.


How can I fix it?

usb – Mouse randomly lags, clicks don’t register on Windows 10/64-bit

Every so often, the mouse cursor will stop responding to mouse movements, mouseclicks don’t register with the system. It seems that the mouse movements/clicks are being buffered to some extent because they eventually register, at least sometimes.

This is with any of several USB mice (Microsoft, Logitech) with the mouse dongle plugged into various ports, front and back and even a powered hub. Same mice work OK on other computers. I’ve noticed no issues with other USB devices on this PC.

When the problem arises, I usually check the process list in TaskMan and never see anything unusual; CPU < 8% or so, no other resources getting pounded. And it seems that the problem often self-corrects when I start TaskMan. A delusion, perhaps.

As a test and out of pure frustration, I just plugged in a wired mouse and (so far) haven’t experienced any issues. I’ll live with it if I must; beats using the PC for a boat anchor, esp. as I don’t have a boat.


Win10/64 Pro on Lenovo M910T (a desktop PC)

NVidia Geoforce GT730 video

i7, 64gb

germany – How to register with the ALDI talk mobile app?

I write this answer as it might help someone in the future – this is slightly weird. My Apple account is created in the USA, so, I assumed if I changed that to Germany, it will surely work out. This turns out not to be true.

Then I used the link posted an earlier answer for the iOS German ALDI talk app. The link is here and I was not able to open it in the iPhone app store and it provides the message as the app is not available in my region or country. Mind it the iTunes account is set to Germany at the time. I don’t get this.

enter image description here

Finally, I did a Google search and ended up in the page Chip.de. The page link is provided here.

enter image description here

I clicked the link and it downloaded and opened the same German app provided earlier. This time I was able to install it in the iPhone and rest of the process went seamlessly.

The app has a rating of 2.5 but it works just fine. Only the process of installation is not very convenient.

air travel – Will I need to register my arrival in Germany when airside transiting through the UK?

In about one month, I will move from my current place of residence back to Germany, my country of citizenship. My flight includes a stopover at London Heathrow airport (I will change planes).

Currently, the country I live in has not been declared a high-risk area by the RKI. Thus, if I were to take a direct flight from here to Germany, I would not need to fill in the digital entry registration. The UK on the other hand – especially England, especially London – is classified as a high-risk area. The landing page of the web form states:

You are not required to complete digital registration on entry if one of the following applies:

  • you only passed through a risk area without a stopover,

As the potentially legally more important German version uses a word (Zwischenaufenthalt) that I might consider closer to (overnight) layover rather than stopover, it’s leading me to assume it may not be required to fill in this form as I am only transiting for a couple of hours. On the other hand, one might also interpret this phrase as applying only to cases such as driving through a high-risk area without stopping. This leaves me a little unsure whether I should fill in the form or not.

(I tried going through the form as far as possible without committing – my arrival is still too far in the future – but I’m still unsure.)

As it is impossible for all of us to say what the situation will be in a month’s time: based on today’s information and regulations, would I have to fill in the digital entry registration if I arrive from a non-high-risk area but transit airside in a high-risk area?

Register visits of my pages in wordpresss

I have a shortcode that obtains the name of the person logged into wordpress, I would like that shortcode when the person enters a page where I have my shortcode create a .text file and save their name inside it

this is my wordpress shortcode

function alertaLogin( $atts ) {
    global $current_user, $user_login;
    add_filter('widget_text', 'apply_shortcodes');
    if ($user_login)
        return 'hola ' . $current_user->display_name;
        return 'no ha iniciado session';
add_shortcode( 'shortcode_login', 'alertaLogin' );

How can I create a .txt from this shortcode to store data within it ???