Robbie's Perl Programming Blog

For those not familiar with "The Weekly Challenge", it is a weekly programming puzzle with two parts, with a new pair of tasks each Monday. You can find it here: The Weekly Challenge The Weekly Challenge for the week of 2026-01-19 through 2026-01-25 is #357. The tasks for challenge #357 are as follows: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Task 357-1: Kaprekar Constant Submitted by: Mohammad Sajid Anwar Write a function that takes a 4-digit integer and returns how many iterations of the following algorithm are required to reach Kaprekar’s constant (6174). (For more information about Kaprekar's Constant, see "https://en.wikipedia.org/wiki/6174".) 1. Select any four-digit number that has at least two different digits (leading zeros are allowed). 2. Create two new four-digit numbers by arranging the original digits in a.) ascending and b.) descending order (adding leading zeros if necessary). 3. Subtract...

For those not familiar with "The Weekly Challenge", it is a weekly programming puzzle with two parts, with a new pair of tasks each Monday. You can find it here: The Weekly Challenge The Weekly Challenge for the week of 2026-01-12 through 2026-01-18 is #356. The tasks for challenge #356 are as follows: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Task 356-1: Kolakoski Sequence Submitted by: Mohammad Sajid Anwar You are given an integer, $int > 3. Write a script to generate the Kolakoski Sequence of given length $int and return the count of 1 in the generated sequence. Please follow the wikipedia page for more informations. Example #1: Input: $int = 4 Output: 2 (1)(22)(11)(2) => 1221 Example #2: Input: $int = 5 Output: 3 (1)(22)(11)(2)(1) => 12211 Example #3: Input: $int = 6 Output: 3 (1)(22)(11)(2)(1)(22) => 122112 Example #4: Input: $int = 7 Output: 4 (1)(22)(11)(2)(1)(22)(1) => 1221121 Example #5: Input: $int = 8 Output: 4 (1)(2...

For those not familiar with "The Weekly Challenge", it is a weekly programming puzzle with two parts, with a new pair of tasks each Monday. You can find it here: The Weekly Challenge The Weekly Challenge for the week of 2026-01-05 through 2026-01-11 is #355. The tasks for challenge #355 are as follows: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Task 355-1: Thousand Separator Submitted by: Mohammad Sajid Anwar You are given a positive integer, $int. Write a script to add thousand separator, "," and return as string. Example #1: Input: $int = 123 Output: "123" Example #2: Input: $int = 1234 Output: "1,234" Example #3: Input: $int = 1000000 Output: "1,000,000" Example #4: Input: $int = 1 Output: "1" Example #5: Input: $int = 12345 Output: "12,345" I'll write a subroutine which splits each integer to its decimal digits, then pops each digit from the right end of the array and append...

For those not familiar with "The Weekly Challenge", it is a weekly programming puzzle with two parts, with a new pair of tasks each Monday. You can find it here: The Weekly Challenge The Weekly Challenge for the week of 2025-12-29 through 2026-01-04 is #354. The tasks for challenge #354 are as follows: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Task 354-1: Min Abs Diff Submitted by: Mohammad Sajid Anwar You are given an array of distinct integers. Write a script to find all pairs of elements with the minimum absolute difference. Rules (a,b): 1: a, b are from the given array. 2: a < b 3: b - a = min abs diff any two elements in the given array # Example inputs and corresponding expected outputs: ( # Example #1 input: [4, 2, 1, 3], # Expected output: [1, 2], [2, 3], [3, 4] # Example #2 input: [10, 100, 20, 30], # Expected output: [10, 20], [20, 30] # Example #3 input: [-5, -2, 0, 3], # Expected output: [-2, 0] # E...

For those not familiar with "The Weekly Challenge", it is a weekly programming puzzle with two parts, with a new pair of tasks each Monday. You can find it here: The Weekly Challenge The Weekly Challenge for the week of 2025-12-22 through 2025-12-28 is #353. The tasks for challenge #353 are as follows: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Task 353-1: Max Words Submitted by: Mohammad Sajid Anwar You are given an array of sentences. Write a script to return the maximum number of words that appear in a single sentence. Example #1: Input: ("Hello world", "This is a test", "Perl is great") Output: 4 Example #2: Input: ("Single") Output: 1 Example #3: Input: ("Short", "This sentence has six words in total", "A B C", "Just four words here") Output: 7 (The second sentence lied.) Example #4: Input: ("One", ...

For those not familiar with "The Weekly Challenge", it is a weekly programming puzzle with two parts, with a new pair of tasks each Monday. You can find it here: The Weekly Challenge The Weekly Challenge for the week of 2025-12-15 through 2025-12-21 is #352. The tasks for challenge #352 are as follows: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Task 352-1: Match String Submitted by: Mohammad Sajid Anwar You are given an array of strings. Write a script to return all strings that are a substring of another word in the given array in the order they occur. Example #1: Input: ("cat", "cats", "dog", "dogcat", "dogcat", "rat", "ratcatdogcat") Output: ("cat", "dog", "dogcat", "rat") Example #2: Input: ("hello", "hell", "world", "wor", "ellow", "elloworld") Output: ("hell", ...