This C++ program solves the N-Queens problem using a stack-based approach with backtracking. It finds and prints all possible solutions for placing N queens on an N×N chessboard such that no two queens threaten each other.

1. Compile and Run:

   Compile the program using a C++ compiler and run the executable. Follow the prompts to enter the value of N.

2. Input:

   • Ensure N is greater than 3 and less than or equal to 20 (maxNval).
   • Example: Enter the value of N (N > 3 and N <= 20): 8

3. Output:

   The program will print all solutions for placing N queens on the chessboard.

• NQueens.cpp: C++ source code for the N-Queens solver.
• README.txt: This file, providing instructions and information about the program.

• NQueens.cpp contains the C++ code for solving the N-Queens problem. It uses a stack-based approach with backtracking to find solutions.

• The program includes the necessary header files (iostream and vector) and defines a Stack structure for stack operations.

• Functions:

  • isSafe: Checks if it's safe to place a queen at a specific position on the board.
  • printBoard: Prints the chessboard with queens represented as "Q" and empty cells as "*".
  • solveNQueens: Solves the N-Queens problem using a stack-based approach with backtracking.