Multiply Linked Lists
Given two numbers represented by linked lists. Your task is to find the multiplied list and return the head of the multiplied list.

The multiplied list is a linked list representation of the multiplication of two numbers.

Input Format:

The first line of input contains a single integer T, representing the number of test cases or queries to be run. Then the T test cases follow. The first line of each test case contains the elements of the first singly linked list separated by a single space and terminated by -1. Hence, -1 would never be a list element. The second line of each test case contains the elements of the second singly linked list separated by a single space and terminated by -1. Hence, -1 would never be a list element.

Output Format:

For each test case, print the multiplied linked list. The elements of the multiplied list should be single-space separated, terminated by -1. The output of each test case is printed in a separate line.

Note :

You do not need to print anything, it has already been taken care of. Just implement the given function.

Constraints :

1

Question

Multiply Linked Lists

Given two numbers represented by linked lists. Your task is to find the multiplied list and return the head of the multiplied list.

The multiplied list is a linked list representation of the multiplication of two numbers.

Input Format:

The first line of input contains a single integer T, representing the number of test cases or queries to be run. 

Then the T test cases follow.

The first line of each test case contains the elements of the first singly linked list separated by a single space and terminated by -1. Hence, -1 would never be a list element.

The second line of each test case contains the elements of the second singly linked list separated by a single space and terminated by -1. Hence, -1 would never be a list element.

Output Format:

For each test case, print the multiplied linked list. The elements of the multiplied list should be single-space separated, terminated by -1.

The output of each test case is printed in a separate line.

Note :

You do not need to print anything, it has already been taken care of. Just implement the given function.

Constraints :

1 <= T <= 10
1 <= N, M <= 100
0 <= data <= 9

Where N and M are the number of nodes in the two linked lists.

Time Limit: 1 sec

Accepted Answer

class solution {
public:
    long long multiplyTwoLists(Node *first, Node *second) {
        const long long mod = 1000000007; // 1e9 + 7
        long long n1 = 0;
        long long n2 = 0;
        
        Node* temp1 = first;
        Node* temp2 = second;
        
        while(temp1) {
            n1 = (n1 * 10 + temp1->data) % mod;
            temp1 = temp1->next;
        }
        
        while(temp2) {
            n2 = (n2 * 10 + temp2->data) % mod;
            temp2 = temp2->next;
        }
        
        return (n1 * n2) % mod;
    }
};