There are three programs.
All of them solves the n-queen problem using brute force method.
The user determines wether queens are placed randomly, one in each column or one in each row and one in each column.
The "place_N_queens... " programs achieve that.
"n_queens" finds the solution, and "n_queens_avg" executes the program multiple times and calculates the average number of attempts.
The "find_attacks_gen" finds the number of attacks for the board. The solution is found when the number of attacks drops to zero.