Generate random chess position
The purpose of this task is to generate a random chess position in FEN format. The position does not have to be realistic or even balanced, but it must comply to the following rules:
- there is one and only one king of each color (one black king and one white king);
- the kings must not be placed on adjacent squares;
- there can not be any pawn in the promotion square (no white pawn in the eighth rank, and no black pawn in the first rank);
- including the kings, up to 32 pieces of either color can be placed. There is no requirement for material balance between sides; The picking of pieces does not have to comply to a regular chess set : there can be five knights, twenty rooks, whatever... as long as the total number of pieces do not exceed thirty-two.
- it is white's turn, it is assumed that both sides have lost castling rights and that there is no possibility for en passant (the FEN should thus end in w - - 0 1);
Generate random chess position is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.
No requirement is made regarding the probability distribution of your method, but your program should be able to span a reasonably representative sample of all possible positions. For instance, programs that would always generate positions with say five pieces on the board, or with kings on a corner, would not be considered truly random.