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Add Two Integers Represented by Linked Lists

Add Two Integers Represented by Linked Lists

Given the head pointers of two linked lists where each linked list represents an integer number (each node is a digit), add them and return the resulting number in a linked list.

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Statement

We are given the head pointers of two linked lists, each linked list represents an integer number (each node is a digit). Add them and return the resulting linked list (i.e., sum).

Here, the first node in a list represents the least significant digit.

Example

g head3 result head a3 8 head3->a3 b3 3 a3->b3 c3 1 b3->c3 d3 0 c3->d3 e3 1 d3->e3 f3 NULL e3->f3 head2 head2 a2 7 head2->a2 b2 3 a2->b2 c2 2 b2->c2 d2 NULL c2->d2 head1 head1 a1 1 head1->a1 b1 0 a1->b1 c1 9 b1->c1 d1 9 c1->d1 e1 NULL d1->e1

Sample input

[1, 0, 9, 9]
[7, 3, 2]

Expected output

[8, 3, 1, 0, 1]

Constraints

Only one positive digit (between 00 and 99 ...