The weekly challenge 368 - Task 1: Make it Bigger

 1 #!/usr/bin/env perl
 2 # https://theweeklychallenge.org/blog/perl-weekly-challenge-368/#TASK1
 3 #
 4 # Task 1: Make it Bigger
 5 # ======================
 6 #
 7 # You are given a given a string number and a character digit.
 8 #
 9 # Write a script to remove exactly one occurrence of the given character digit
10 # from the given string number, resulting the decimal form is maximised.
11 #
12 ## Example 1
13 ##
14 ## Input: $str = "15456", $char = "5"
15 ## Output: "1546"
16 ##
17 ## Removing the second "5" is better because the digit following it (6) is
18 ## greater than 5. In the first case, 5 was followed by 4 (a decrease),
19 ## which makes the resulting number smaller.
20 #
21 ## Example 2
22 ##
23 ## Input: $str = "7332", $char = "3"
24 ## Output: "732"
25 #
26 ## Example 3
27 ##
28 ## Input: $str = "2231", $char = "2"
29 ## Output: "231"
30 ##
31 ## Removing either "2" results in the same string here. By removing a "2",
32 ## we allow the "3" to move up into a higher decimal place.
33 #
34 ## Example 4
35 ##
36 ## Input: $str = "543251", $char = "5"
37 ## Output: "54321"
38 ##
39 ## If we remove the first "5", the number starts with 4. If we remove the
40 ## second "5", the number still starts with 5. Keeping the largest possible
41 ## digit in the highest place value is almost always the priority.
42 #
43 ## Example 5
44 ##
45 ## Input: $str = "1921", $char = "1"
46 ## Output: "921"
47 #
48 ############################################################
49 ##
50 ## discussion
51 ##
52 ############################################################
53 #
54 # Simplicity beats complexity: Just create all possible variations of numbers
55 # by removing each possible occurrence of $char and remember the biggest one
56 # of those.
57 
58 use v5.36;
59 
60 make_it_bigger("15456", "5");
61 make_it_bigger("7332", "3");
62 make_it_bigger("2231", "2");
63 make_it_bigger("543251", "5");
64 make_it_bigger("1921", "1");
65 
66 sub make_it_bigger($str, $char) {
67     say "Input: \"$str\", \"$char\"";
68     my @chars = split //, $str;
69     my $best = 0;
70     foreach my $index (0..$#chars) {
71         if($chars[$index] eq $char) {
72             my $tmp = join("", @chars[0..$index-1]) . join("", @chars[$index+1..$#chars]);
73             $best = $tmp if $tmp > $best;
74         }
75     }
76     say "Output: $best";
77 }