#!/usr/bin/perl

use strict; use warnings;
print my $lookfor = '10.73.138.11', "\n\n";
print /\b\Q$lookfor\E\b/ ? "matches $_\n" : "fails $_\n"
  for qw( 110.73.138.11 10.73.138.11 10.73.138.111 10.735138.11 );