PWC 248 Task 1 complete

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+#!/usr/bin/env perl
+# vim:set ts=4 sw=4 sts=4 et ai wm=0 nu:
+#=============================================================================
+# Copyright (c) 2023, Bob Lied
+#=============================================================================
+# ch-1.pl Perl Weekly Challenge 248 Task 1 Shortest Distance
+#=============================================================================
+# You are given a string and a character in the given string.
+# Write a script to return an array of integers of size same as length of
+# the given string such that:
+# distance[i] is the distance from index i to the closest occurence of
+# the given character in the given string.
+# The distance between two indices i and j is abs(i - j).
+# Example 1 Input: $str = "loveleetcode", $char = "e"
+#           Output: (3,2,1,0,1,0,0,1,2,2,1,0)
+#   The character 'e' appears at indices 3, 5, 6, and 11 (0-indexed).
+#   The closest occurrence of 'e' for index 0 is at index 3,
+#   so the distance is abs(0 - 3) = 3.
+#   The closest occurrence of 'e' for index 1 is at index 3,
+#   so the distance is abs(1 - 3) = 2.
+#   For index 4, there is a tie between the 'e' at index 3 and 'e' at index 5,
+#   but the distance is still the same: abs(4 - 3) == abs(4 - 5) = 1.
+#   The closest occurrence of 'e' for index 8 is at index 6,
+#   so the distance is abs(8 - 6) = 2.
+# Example 2 Input: $str = "aaab", $char = "b"
+#           Output: (3,2,1,0)
+#=============================================================================
+
+use v5.38;
+
+use builtin qw/true false/; no warnings "experimental::builtin";
+
+use List::Util qw/min/;
+
+use Getopt::Long;
+my $Verbose = 0;
+my $DoTest  = 0;
+
+GetOptions("test" => \$DoTest, "verbose" => \$Verbose);
+exit(!runTest()) if $DoTest;
+
+say "(", join(",", shortest(@ARGV)->@*), ")";
+
+sub shortest($str, $char)
+{
+    my @dist;
+    my @s = split //, $str; # str as vector of characters
+
+    # List of indexes where char appears
+    my @cloc = grep { $s[$_] eq $char } 0 .. $#s;
+
+    for my $i ( 0 .. $#s )  # For each letter in str
+    {
+        #               List of location differences
+        #               vvvvvvvvvvvvvvvvvvvvvvvvvvvv
+        push @dist, min map { abs($_ - $i) } @cloc;
+    }
+    return \@dist;
+}
+
+sub runTest
+{
+    use Test2::V0;
+
+    is( shortest("loveleetcode", 'e'), [3,2,1,0,1,0,0,1,2,2,1,0], "Example 1");
+    is( shortest("aaab", 'b'), [3,2,1,0], "Example 2");
+
+    is( shortest("ab", 'x'), [undef, undef], "no x in str");
+    is( shortest("", 'x'), [], "empty string");
+
+    done_testing;
+}