README FOR RECURSIVE SUDOKU SOLVER *as the hackerrank requirement is to make the code as compact as possible, sudoku.cpp is basically a two-line program, please refer to sudoku_readable.cpp for clearer presentation. Input: N xxxxxxxxx xxxxxxxxx xxxxxxxxx xxxxxxxxx xxxxxxxxx xxxxxxxxx xxxxxxxxx xxxxxxxxx xxxxxxxxx ------------------------------ N = no. test cases x = number from 1 - 9 (9x9 per test case)