Given a partially filled 9×9 2D array ‘grid[9][9]’, the goal is to assign digits (from 1 to 9) to the empty cells so that every row, column, and subgrid of size 3×3 contains exactly one instance of the digits from 1 to 9.
Input: In a text file, the user is required to enter a 9x9 Sudoku matrix with blank spaces represented by a Zero(0)
Use [gcc] (https://gcc.gnu.org/) to install gcc.
sudo apt install gcc-9gcc main.c
./a.out