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+#!/usr/bin/env perl
+# vim:set ts=4 sw=4 sts=4 et ai wm=0 nu:
+#=============================================================================
+# ch-1.pl Perl Weekly Challenge 235 Task 1 Remove One 
+#=============================================================================
+# Copyright (c) 2023, Bob Lied
+#=============================================================================
+# You are given an array of integers.
+# Write a script to find out if removing ONLY one integer makes it
+# strictly kincreasing order.
+# Example 1 Input: @ints = (0, 2, 9, 4, 6)
+#           Output: true
+#   Removing ONLY 9 in the given array makes it strictly increasing order.
+# Example 2 Input: @ints = (5, 1, 3, 2)
+#           Output: false
+# Example 3 Input: @ints = (2, 2, 3)
+#           Output: true
+#=============================================================================
+
+use v5.38;
+use builtin qw(true false); no warnings "experimental::builtin";
+
+use Getopt::Long;
+my $Verbose = 0;
+my $DoTest  = 0;
+
+GetOptions("test" => \$DoTest, "verbose" => \$Verbose);
+exit(!runTest()) if $DoTest;
+
+# Move down the list in pairs and count the number of times that
+# we find a decreasing pair.  Stop when we hit the second one.
+sub removeOne(@ints)
+{
+    my $rmvCount = 0;
+    for ( my $i = 0; $i < $#ints && $rmvCount < 2 ; $i++ )
+    {
+        $rmvCount++ if $ints[$i+1] < $ints[$i];
+    }
+    return $rmvCount < 2;
+}
+
+# Map each pair to true/false for being sorteed ascending.  Count the falses.
+# Will be inefficient if the list is long and the out-of-order elements are
+# near the front.
+sub ro_A(@ints)
+{
+    my $rmvCount = grep { $_ == false } map { $ints[$_] < $ints[$_+1] } 0 .. ( $#ints-1 );
+    return $rmvCount < 2;
+}
+
+# Slide down the list in pairs and count the number of items that
+# are out of order.  Always scans the whole list.
+sub ro_B(@ints)
+{
+    use List::MoreUtils qw/slide/;
+    my $rmvCount = 0;
+    slide { $rmvCount++ if ( $b < $a ) } @ints;
+    return $rmvCount < 2;
+}
+
+# Use try/catch to quit early from slide
+sub ro_C(@ints)
+{
+    use List::MoreUtils qw/slide/;
+    use feature 'try'; no warnings "experimental::try";
+    my $rmvOne = true;
+    try {
+        my $rmvCount = 0;
+        slide { do { die if ++$rmvCount > 1 } if ( $b < $a ) } @ints;
+    }
+    catch ($e)
+    {
+        $rmvOne = false;
+    }
+    return $rmvOne;
+}
+
+sub runTest
+{
+    use Test2::V0;
+    no warnings "experimental::builtin";
+
+    is( removeOne(0,2.9,4,6), true,  "Example 1");
+    is( removeOne(5,1,3,2  ), false, "Example 2");
+    is( removeOne(2,2,3    ), true,  "Example 3");
+
+    is( ro_A(0,2.9,4,6), true,  "Example 1");
+    is( ro_A(5,1,3,2  ), false, "Example 2");
+    is( ro_A(2,2,3    ), true,  "Example 3");
+
+    is( ro_B(0,2.9,4,6), true,  "Example 1");
+    is( ro_B(5,1,3,2  ), false, "Example 2");
+    is( ro_B(2,2,3    ), true,  "Example 3");
+
+    is( ro_C(0,2.9,4,6), true,  "Example 1");
+    is( ro_C(5,1,3,2  ), false, "Example 2");
+    is( ro_C(2,2,3    ), true,  "Example 3");
+
+    done_testing;
+}