| 04 April 2025 | Challenge 315 |
The Third Index
Task 1: Find Words
Submitted by: Mohammad Sajid Anwar
You are given a list of words and a character.
Write a script to return the index of word in the list where you find the given character.
Example 1
Input: @list = ("the", "weekly", "challenge")
$char = "e"
Output: (0, 1, 2)
Example 2
Input: @list = ("perl", "raku", "python")
$char = "p"
Output: (0, 2)
Example 3
Input: @list = ("abc", "def", "bbb", "bcd")
$char = "b"
Output: (0, 2, 3)
Solution
Using a regex to search for the given character extends the solution to finding substrings.
use strict;
use warnings;
use List::MoreUtils 'indexes';
sub find_words {
my $c = shift;
indexes {/\Q$c\E/} @_;
}
See the full solution to task 1.
Task 2: Find Third
Submitted by: Mohammad Sajid Anwar
You are given a sentence and two words.
Write a script to return all words in the given sentence that appear in sequence to the given two words.
Example 1
Input: $sentence = "Perl is a my favourite language but Python is my favourite too."
$first = "my"
$second = "favourite"
Output: ("language", "too")
Example 2
Input: $sentence = "Barbie is a beautiful doll also also a beautiful princess."
$first = "a"
$second = "beautiful"
Output: ("doll", "princess")
Example 3
Input: $sentence = "we will we will rock you rock you.",
$first = "we"
$second = "will"
Output: ("we", "rock")
Solution
Some assumptions:
- words are separated by single
spacecharacters - a word in the sentence must match with a given word completely, i.e. when the word
"be"is given, the word"robe"in the sentence does not match.
use v5.30;
use warnings;
use experimental qw(signatures vlb);
sub find_third ($first, $second, $sentence) {
$sentence =~ /(?<=(?:^|\W)$first $second )(\w+)/g;
}
See the full solution to task 2.
If you have a question about this post or if you like to comment on it, feel free to open an issue in my github repository.