AddTwoNumbersRepresentedByLinkedList_Geeks.txt

class Solution
{
    public:
    //Function to add two numbers represented by linked list.
    struct Node* addTwoLists(struct Node* first, struct Node* second)
    {
        //code here
       int carry=0,sum=0;
       Node *temp;
       Node* head1=reverse(first);
       Node* head2=reverse(second);
       Node* head3 =  addtwonumbers(head1,head2);
       return reverse(head3);
    }
    
    struct Node* addtwonumbers(struct Node* first,struct Node* second)
    {
       Node *res=NULL;
       int sum =0;
       int carry=0;
       Node *pre=NULL;
       Node *temp;
       while(first!=NULL || second!=NULL)
       {
           sum=carry+(first?first->data:0)+(second?second->data:0);
           carry=(sum>=10)?1:0;
           sum=sum%10;
           temp=new Node(sum%10);
          if(res==NULL)
          res=temp;
          else
           pre->next=temp;
          pre=temp;
           if(first)
           first=first->next;
           if(second)
           second=second->next;
           
       }
       if(carry)
       temp->next=new Node(carry);
       return res;
       
    }
    struct Node* reverse(struct Node* head)
    {
        Node* pre=NULL;
        Node* next;
        Node* current=head;
        while(current!=NULL)
        {
            next=current->next;
            current->next=pre;
            pre=current;
            current=next;
        }
        head=pre;
        return head;
    }
};