InterviewBit Problems   Valid Sudoku : Unsolved

About the Valid Sudoku : Unsolved category (1)
Wrong output when submitting but correct when run as custom input (2)
What is the error in this code (1)
C++ solution without using cube (1)
How it's output will be 1 (3)
Is it always a 9*9 board? (3)
C++ : vector. resize() does not reset (1)
Nice problem for using hash table (1)
Identation is messed up (1)