Hello :) Consider this bit of code. 
my $stri="abctest";

my @one=('a','b','c','d','e','f','g');
                                   
my $part;

my $lone=@one;                                   
my $first_char=substr($stri,0,1);   
#print "\n$first_char";
my $second_char=substr($stri,1,1);
#print "\n$second_char";
my $third_char=substr($stri,2,1);
#print "\n$third_char"; 

if ($first_char eq 'a' || $first_char eq 'b'){ 

  for(my $ne=0;$ne<$lone;$ne++){
    
    if ($second_char eq $one[$ne])  
     {                                    
    
      if ($third_char ne 'c' || $third_char ne 'd'){
       
         $part=substr($stri,0,2); 
         print "\nThe string in part:";
         print"\n$part";
        
        }
     }
  
   } 
 
}

 
if ($first_char eq 'a' || $first_char eq 'b'){ 

  for(my $ne=0;$ne<$lone;$ne++){
    
    if ($second_char eq $one[$ne]){    
    
      if ($third_char eq 'c' || $third_char eq 'd'){
                                       
        $part=substr($stri,0,3); 
        print "\nThe string in part:";
        print"\n$part";
      }
      
     }
  
   } 
 
}

[download]
When we run the above code with $stri equal to "abctest" we should get a match in the second section of loops only
i.e. if the first char in the string is 'a' or 'b' , second char is any of the elements of @one, and third char is 'c' or 'd'.
The value of part should be 'abc'.

But there is a match in both the sections of loops, and this is the output I get: 
The string in part:
ab
The string in part:
abc

[download]
This comparison does not seem to be working: 
if ($third_char ne 'c' || $third_char ne 'd'){
$part=substr($stri,0,2);

[download]
What is the mistake here?
Thanx :)

In reply to Loops and comparisons by perl_seeker

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