#!/usr/bin/perl

use warnings;
use strict;

my $wordcount  = 0;
my $linenumber = 0;
my $wordnumber = 0;
my $findword  = "and";

open(FILE, "< input.txt") or die "Cannot open file: $!";
my @lines = <FILE>;
close(FILE) or die "Cannot close file: $!";

foreach my $line (@lines)
{
    $linenumber++;
   
    my @words = split(/\s+/, $line);

    foreach my $word (@words)
    {
       $wordnumber++;

       if ($word =~ m/^and$/)
       {
           print qq(The word "$findword" occured in line $linenumber a
+t word $wordnumber\n);
       }
    }
       $wordnumber = 0;
}
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UPDATE: Fixed word splitting in regards to Enlil's message:

"but split '',$line is probably better than / /, if someone puts two spaces you might want split, / +/,$line =) "

Thanks!