The weekly challenge 362 - Task 1: Echo Chamber

 1 #!/usr/bin/env perl
 2 # https://theweeklychallenge.org/blog/perl-weekly-challenge-362/#TASK1
 3 #
 4 # Task 1: Echo Chamber
 5 # ====================
 6 #
 7 ## Example 1
 8 ##
 9 ## Input: "abca"
10 ## Output: "abbcccaaaa"
11 ##
12 ## Index 0: "a" -> repeated 1 time  -> "a"
13 ## Index 1: "b" -> repeated 2 times -> "bb"
14 ## Index 2: "c" -> repeated 3 times -> "ccc"
15 ## Index 3: "a" -> repeated 4 times -> "aaaa"
16 #
17 #
18 ## Example 2
19 ##
20 ## Input: "xyz"
21 ## Output: "xyyzzz"
22 ##
23 ## Index 0: "x" -> "x"
24 ## Index 1: "y" -> "yy"
25 ## Index 2: "z" -> "zzz"
26 #
27 #
28 ## Example 3
29 ##
30 ## Input: "code"
31 ## Output: "coodddeeee"
32 ##
33 ## Index 0: "c" -> "c"
34 ## Index 1: "o" -> "oo"
35 ## Index 2: "d" -> "ddd"
36 ## Index 3: "e" -> "eeee"
37 #
38 #
39 ## Example 4
40 ##
41 ## Input: "hello"
42 ## Output: "heelllllllooooo"
43 ##
44 ## Index 0: "h" -> "h"
45 ## Index 1: "e" -> "ee"
46 ## Index 2: "l" -> "lll"
47 ## Index 3: "l" -> "llll"
48 ## Index 4: "o" -> "ooooo"
49 #
50 #
51 ## Example 5
52 ##
53 ## Input: "a"
54 ## Output: "a"
55 ##
56 ## Index 0: "a" -> "a"
57 #
58 ############################################################
59 ##
60 ## discussion
61 ##
62 ############################################################
63 #
64 # We pick every character and add it to the output the appropriate
65 # amount of times.
66 
67 use v5.36;
68 
69 echo_chamber("abca");
70 echo_chamber("xyz");
71 echo_chamber("code");
72 echo_chamber("hello");
73 echo_chamber("a");
74 
75 sub echo_chamber($str) {
76     say "Input: $str";
77     my @chars = split //, $str;
78     my $out = "";
79     foreach my $i (1..$#chars+1) {
80         $out .= $chars[$i-1] x $i;
81     }
82     say "Output: $out";
83 }
84