Xah Talk Show 2025-12-15 Ep725 Wolfram Language, Advent of Code 2025, Day 2, Problem 2

https://youtu.be/W2C4oaU3-yo

Video Summary (Generated by AI, Edited by Human.)

Here's a breakdown of the topics discussed in the video with their corresponding timestamps:

Solving Advent of Code 2025, Day 2, Problem 2 with Wolfram Language: (0:03)
Discussion and Review of the Ultimate Hacking Keyboard 80 (UHK80): (0:16)
Introduction to Wolfram Language for Programmers: (1:21)
Comparison of Wolfram Language with AI Chatbots (like ChatGPT): (4:40)
Wolfram Language's Advanced Capabilities for Mathematical Computations: (3:05)
Wolfram Language for Handling Complex Scientific and Data-Driven Queries: (7:29)
Problem Description: Identifying Numbers with Repeated Digit Sequences: (17:17)
Limitations of Advent of Code Problem Specifications (lack of maximum digit info): (29:39)
Impact of Undefined Maximum Digits on Coding Solutions: (30:01)
Is Ultimate Hacking Keyboard 80 (UHK80) worth buying, vs Kinesis Freestyle and Glove 80 and others (40:26).
Solution using Regular Expressions with Test Cases: (55:00-55:51)

Solve Advent of Code 2025, Day 2, Problem 2 using Wolfram Language (0:03).
Problem: identifying numbers that are sequences of digits repeated at least twice (17:17).

Wolfram Language vs AI chatbots ChatGPT. (1:21) (4:40).
Highlights Wolfram Language's advanced capabilities for mathematical computations (3:05) and its ability to handle complex scientific and data-driven queries (7:29).
Chatbots are more versatile for general questions (6:03), Wolfram Language provides more accurate and technical information for scientific problems (1:51).

Is Ultimate Hacking Keyboard 80 (UHK80) worth buying (0:16), vs Kinesis Freestyle and Glove 80 and others (40:50).
Insights on factors to consider when purchasing an expensive keyboard, such as price, portability, and desired features (45:00).

criticism of Advent of Code (29:39). e.g. no mention of the maximum number of digits in the input, which affects the approach to coding solutions (30:01).

Near the end, shown solution is just one line of code, at the core is a regular expression (55:00-55:51).

Wolfram language vs ai chatbot
https://youtu.be/W2C4oaU3-yo?t=280

https://adventofcode.com/2025/day/2

xah talk show ep725 Wolfram language 206c7

Code

xinput = "8123221734-8123333968,2665-4538,189952-274622,4975-9031,24163352-24202932,1233-1772,9898889349-9899037441,2-15,2147801-2281579,296141-327417,8989846734-8989940664,31172-42921,593312-632035,862987-983007,613600462-613621897,81807088-81833878,13258610-13489867,643517-782886,986483-1022745,113493-167913,10677-16867,372-518,3489007333-3489264175,1858-2534,18547-26982,16-29,247-366,55547-103861,57-74,30-56,1670594-1765773,76-129,134085905-134182567,441436-566415,7539123416-7539252430,668-1146,581563513-581619699";

StringMatchQ[ "121212" , RegularExpression[ "(\\d+)\\1"] ]
(* False *)

StringMatchQ[ "121212" , RegularExpression[ "(\\d+)\\1\\1" ] ]
(* True *)

StringMatchQ[ "121212" , RegularExpression[ "((\\d+)\\1\\1)" ] ]
(* False *)

StringMatchQ[ "121212" , RegularExpression[ "(\\d+)\\1|(\\d+)\\1\\1" ] ]
(* False *)

(* s------------------------------ *)

StringMatchQ[ "121212" , RegularExpression[ "(\\d+)\\1\\1" ] ]
(* True *)

StringMatchQ[ "121212" , RegularExpression[ "(?:(\\d+)\\1\\1)" ] ]
(* True *)

(* s------------------------------ *)

StringMatchQ[ "121212" , RegularExpression[ "(\\d+)\\1{1,20}" ] ]
(* True *)

StringMatchQ[ "12121212" , RegularExpression[ "(\\d+)\\1{1,20}" ] ]
(* True *)

StringMatchQ[ "1212" , RegularExpression[ "(\\d+)\\1{1,20}" ] ]
(* True *)

StringMatchQ[ "12123" , RegularExpression[ "(\\d+)\\1{1,20}" ] ]
(* False *)

(* s------------------------------ *)

(* xinput = "11-22,95-115,998-1012,1188511880-1188511890,222220-222224,1698522-1698528,446443-446449,38593856-38593862,565653-565659,824824821-824824827,2121212118-2121212124"; *)

xinput = "8123221734-8123333968,2665-4538,189952-274622,4975-9031,24163352-24202932,1233-1772,9898889349-9899037441,2-15,2147801-2281579,296141-327417,8989846734-8989940664,31172-42921,593312-632035,862987-983007,613600462-613621897,81807088-81833878,13258610-13489867,643517-782886,986483-1022745,113493-167913,10677-16867,372-518,3489007333-3489264175,1858-2534,18547-26982,16-29,247-366,55547-103861,57-74,30-56,1670594-1765773,76-129,134085905-134182567,441436-566415,7539123416-7539252430,668-1146,581563513-581619699";

xsplitedInput = StringSplit[xinput,","];

newInputList = Map[
Function[x,
Apply[Range , Map[ ToExpression, StringSplit[x,"-"]]]
] ,
xsplitedInput];

Total @ Flatten @
Map[
Function[xnumberList,
 Select[xnumberList,
  Function[x,
   StringMatchQ[ ToString[x] ,
RegularExpression[ "(\\d+)\\1{1,20}" ]
 ]]
]] ,
newInputList
]

(* 76169125915 *)

xinput = "11-22,95-115,998-1012,1188511880-1188511890,222220-222224,1698522-1698528,446443-446449,38593856-38593862,565653-565659,824824821-824824827,2121212118-2121212124";

Total @ Flatten @ Map[ Function[xnumberList, Select[xnumberList, Function[x, StringMatchQ[ ToString[x] , RegularExpression[ "(\\d+)\\1{1,20}" ] ]] ]] , Map[ Function[x, Apply[Range , Map[ ToExpression, StringSplit[x,"-"]]] ] , StringSplit[xinput,","]] ]
(* 4174379265 *)

(* s------------------------------ *)

(* shortcut syntax  *)
Total @ Flatten @ ((Select[#, Function[x, StringMatchQ[ ToString[x] , RegularExpression[ "(\\d+)\\1{1,20}" ] ]] ] &) /@ ((Range @@ Map[ ToExpression, StringSplit[#,"-"]] &) /@ StringSplit[xinput,","]) )
(* 4174379265 *)