bad thing is i do not see any debug from doing std::cout
But the code is running and if i change it, i will receive
what it expected isntead.
But no result from std::cout

I think you should make the Instruction more clear by saying the last element will be Null(in java) or null (in C)
but you stated it like file system structure Null/null/NULL.

Another Important thing Stated clear that NULL will be in as a word not like "" or " ".

Thanks

The second example in the instruction has a mistype it shoud 33 not 36.
Kindly correct it.
Thanks.

It was very hard to optimize the solution using the concept of indexed global array.