Welcome to Day 8 of the DSA Coding Challenge:

Today's Goals (Backtracking continued) :

Question 1: Sudoku Solver: Write a program to solve a Sudoku puzzle by filling the empty cells.

A sudoku solution must satisfy all of the following rules:

1.Each of the digits 1-9 must occur exactly once in each row.

2.Each of the digits 1-9 must occur exactly once in each column.

3.Each of the digits 1-9 must occur exactly once in each of the 9 3x3 sub-boxes of the grid.

The '.' character indicates empty cells.

Question 2: N Queens: The n-queens puzzle is the problem of placing n queens on an n x n chessboard such that no two queens attack each other.

Given an integer n, return all distinct solutions to the n-queens puzzle. You may return the answer in any order.

Each solution contains a distinct board configuration of the n-queens' placement, where 'Q' and '.' both indicate a queen and an empty space, respectively.

All the best !