/*
You have two numbers represented by a linked list, where each node contains a single digit. The digits are stored in reverse order, such that the highest order digit is at the head of the list.

Write a function that adds the two numbers and returns the sum as a linked list.

Input format:
First line contains N, number of elements in the first linked list.

Next line contains N space separated integers, elements of that linked list.

First line contains M, number of elements in the second linked list.

Next line contains M space separated integers, elements of that linked list.

Output format
Print the sum of the given numbers.

Sample Input 1
3

7 1 6

3

5 9 2

Sample Output 1
2 1 9

Explanation
617 + 295 = 912

Sample Input 2
2

4 9

2

0 5

Sample Output 2
4 4 1

Explanation
94 + 50 = 144

Sample Input 3
2

1 0

1

2

Sample Output 3
3 0

Explanation
That is, 01 + 2 = 03. Note that we retain the preceding 0 as well.

Constraints
1 <= M, N <= 10^5

*/


/*
class ListNode{
    constructor(val){
        this.val = val;
        this.next = null;
    }
*/

function getSum(str1,n,str2,m){
      let carry=0,i=0,j=0,str='';
      while(i<n&&j<m){
            let sum=parseInt(str1[i])+parseInt(str2[i])
            +carry;
            carry =parseInt(sum/10);
            sum=parseInt(sum%10);
            str=str+(sum).toString();
            i++;
            j++;
      }

      while(i<n){
            let sum=parseInt(str1[i])+carry;
            carry =parseInt(sum/10);
            sum=parseInt(sum%10);
            str=str+(sum).toString();
            i++;
      }

      while(j<m){
            let sum=parseInt(str2[j])+carry;
            carry =parseInt(sum/10);
            sum=parseInt(sum%10);
            str=str+(sum).toString();
            j++;
      }
      if(carry>0){
            str=str+(carry).toString();
      }
      return str;

}

function getFinalList(str){
      let head=null;
      let pointer=null;
      let i=0;
      while(i<str.length){
            const newNode=new ListNode(parseInt(str[i]));
            if(head==null){
                  head=newNode;
                  pointer=head;
            }else{
                  pointer.next=newNode;
                  pointer=pointer.next;
            }
            i++;
      }
      return head;

}
/**
 * @param {ListNode} head1
 * @param {ListNode} head2
 * @return {ListNode}
 */
function sumLists1(head1, head2) {
      let str1='',str2='',str='',head=null,ptr;
      ptr=head1;
      while(ptr!=null){
            str1=str1+(ptr.val).toString();
            ptr=ptr.next;
      }

      ptr=head2;
      while(ptr!=null){
            str2=str2+(ptr.val).toString();
            ptr=ptr.next;
      }

      str=getSum(str1,str1.length,str2,str2.length);
      head=getFinalList(str);
    return head;
}