Hello ,
I am trying to write a code to reverse a singly linked list. But I am not being successful at it.
I was able to create a singly linked list and print it out without any issues , but during the reversal , I am sort of stuck.
Here is my code below , please correct me . I am doing some mistake in my reverse logic
use strict;
use warnings;
use Data::Dumper;


## Singly Linked List
my $head = {
    data => undef,
    next => undef
};

my $curr=$head;

for (my $i=1;$i<5;$i++){
    
    $curr->{next} ={
        data =>$i,
        next =>undef
    };
    
    $curr= $curr->{next};
}

$curr->{next} ={
    data=>undef,
    next=>undef
    
};


$curr=$head;

while(defined($curr->{next})){
    
    print "$curr->{data} \n";
    $curr= $curr->{next};
    
}

$curr=$head;
my $forward;
my $previous;

## Reversing Singly Linked List

while(defined ($curr->{next})){    
    $forward = $curr->{next};
    $curr->{next}=$head;
    $previous=$head;    
    $curr=$forward;
    $head=$curr;
        
}


$curr->{next}=$previous;    


$curr=$head;
## printing the reversed List

while(defined($curr->{next})){
    
    print "enterd \n";
    print "$curr->{data} \n";
    $curr= $curr->{next};
    
}

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In reply to Reversing a singly linked list by punitpawar

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