Solving Sudoku and the 8-Queens Puzzle as Constraint Satisfaction

Constraint satisfaction problems (CSPs) are problems in artificial intelligence and computer science whose solution must satisfy a particular set of constraints. A constraint is a condition or restriction that a solution must meet. CSPs are often used to model problems associated with scheduling, planning, and resource allocation. These problems can be solved using various techniques, including search algorithms, constraint programming, and local search.

A Sudoku board is a 9x9 grid divided into 3x3 sub-grids called regions. The objective is to fill the grid with the digits 1–9 such that each digit appears in each row, column, and region just once. Sudoku is usually presented as a partially completed grid, and the player must fill in the blanks according to the rule above.

The 8-Queens problem is another classic example of a constraint satisfaction problem. The goal is to place eight queens on a chessboard such that no two queens threaten each other. This means that no two queens can be placed on the same row, column, or diagonal.

In this project, we’ll formulate both problems as CSPs and solve them using constraint programming in Python.