Guess / Mastermind
How do black and white feedback pegs work in Guess?
Black feedback counts correct colours in the correct positions. White counts correct colours in different positions. These are totals, not positional labels attached to individual pegs in your guess.
Worked example
One black and one white means two colour matches in total: exactly one has the right position, while the other must move.
What to check on your board
Apply the rule above to your current board, then verify the remaining puzzle constraints. The example explains a local deduction; it is not a solution to every randomly generated board.
Checking your next move
Keep each guess beside its complete black-and-white feedback. A candidate code must explain all previous totals, not just the latest line. Avoid attaching a feedback peg to the same position in the guess; the feedback reports counts rather than a map of the answer.
Using this reference
For Guess / Mastermind, read the rule and the worked example together before opening the game. Separate what the rule explicitly requires from what only seems likely on the current board. A useful next move is one you can explain from the visible constraints, not merely a pattern that looks familiar.
If you get stuck, isolate a smaller part of the position and list what is still possible there. After a move, check the affected rows, regions or connections again. The reference explains the documented rules; progress, controls and save behavior belong to the linked game.
Read the developer’s manual ↗ · Open the developer’s browser version ↗
Manual inspected: · Simon Tatham & contributors · MIT