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The problem is that the MASM 5.10 linker is deficient and doesn't properly handle this kind of 32-bit relocation. As you suspected it is treating the 32-bit relative displacement as a 16-bit value which as you have correctly observed produces the wrong value (notably when calling code at a negative displacement). To test your code I have been using MASM 5.10a and the linker is version 3.64.

You can continue to use MASM.EXE 5.10a, but you will need to replace your linker. The 16-bit Microsoft Overlay Linker (LINK.EXE) that comes with MASM 6.11 does work correctly. You will need to have an expanded memory manager present for the LINK.EXE and/or MASM.EXE to function correctly. MASM 6.11 was the last version of the MASM products that can be run from DOS. MASM 6.11 install disks can be downloaded from here.

If you download and install Borland's Turbo Assembler v2.0x you can assemble your code with TASM and link with TLINK. If you run TLINK on the object file produced by TASM it will actually warn you of this problem! The error will look something like:

32-bit record encountered in module Use "/3" option

If you use the /3 option it enables 32-bit processing and a proper executable should be generated.

To assemble with TASM (it will still work with MASM) a small adjustment must be made to these lines:

You can use maxima for definite integrals using numerical optimization as well as symbolic ones. For example

Ignoring a query is definitively not what you want to do (in normal operation), as the client will then try again, and switch to another nameserver at some point, so at the very least you inflict them delays, if not bad results.

Possible return codes are defined in https://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml#dns-parameters-6 and mostly defined in RFC 1035.

For your case I think you have exactly what you need: REFUSED

It is defined as such:

The name server refuses to perform the specified operation for policy reasons. For example, a name server may not wish to provide the information to the particular requester, or a name server may not wish to perform a particular operation (e.g., zone transfer) for particular data.

Now, your nameserver is authoritative on some domain names. If it receives query for other ones, it should say it is not authoritative for them, which is NXDOMAIN or precisely RCODE 3 defined as such in RFC 1035:

Name Error - Meaningful only for responses from an authoritative name server, this code signifies that the domain name referenced in the query does not exist.

This is a very small answer, hence you are not amplifying anything. Your server could still be hit by many such queries, and you may decide to implement rate limiting (see below). It is true that traffic being UDP your server may answer to a victim not being the true source of the query, but without amplification, and like any other nameserver in the world will do also as this is the sad fate of all UDP-based protocols.

A DDOS would be if you reply to the query with an answer being even larger (like if you tried to replied to ANY, even for the names you are authoritative on), as here a victim could receive a lot of traffic while the attacker would have need very little to send to you.

Also, ANY is more a (bad) troubleshooting tool intended for recursive nameservers (as in "give me the current state of your cache for a specific label") instead of authoritative ones. There are works currently to just deprecate it completely: https://blog.cloudflare.com/what-happened-next-the-deprecation-of-any/

Now you seem more to speak about operational problems, and DDOS attack. This is another case where even replying may be costly. Current nameservers implement a RRL mechanism, for "Response Rate Limiting", basically by reducing the rate of replies. Have a look at this article for Bind that present the feature: https://kb.isc.org/article/AA-01000/0/A-Quick-Introduction-to-Response-Rate-Limiting.html

You may wish to implement something like that for your own nameserver if you fear it could be attacked.

An easy way to hide/show objects in a shiny web app is to use the amazing shinyjs package from Dean Attali. The package is widley documented and you can find a complete set of working examples on this page from Dean's blog.

runcodeUI actually creates a textInput (or textAreaInput etc). Its name is runcode_exp, and you can access it in the regular way:

input$runcode_expr

Do not that this identifier could potentially change in the future (if you use it in many places, you may want to wrap it in a reactive so that it's easy to change later), and of course that runcodeServer is an eval, and therefore a huge security risk.

Here is a solution for your problem.
I start loading your Excel dataset and then define the Outcomes dataset:

The below code worked:

UI.R