https://hack.codingblocks.com/contests/c/424/302
https://ide.codingblocks.com/s/66490
1. runtime error in code
HI Gaurav, please take the input according to specified input format. You are taking N1 first and then building list 1 whereas you have to take N1 then N2 and the build the both lists.
Also a suggestion, in your print function you are changing your head node always by:
head = head->next ;
Although this is working fine because once you display the list the program ends but you should also realize that the head reference to head of list gets lost so you should first make a temporary pointer and then operate on it to print the list so that for future operations it dosen’t get lost.
Hope this helps 
And I have passed head not as reference to print function so original head will remain same
Hi Gaurav, pls upload a screenshot of the problem statement here.
Hi Gaurav, pls see that your code is failing for a testcase where size of 1 list is 0. i.e.:
// Input
1
0
3
2 4 6// Expected Output
2 4 6// Your Output
Runtime Error
Ok got it…thanks
Hey Nargis, I am marking your doubt as Resolved for now. Re-open it if required.
Please mark your doubts as resolved in your course’s “ Ask Doubt ” section, when your doubt is resolved.