The goal is to guess the secret code generated by the game.
Enter the guess using the buttons in the menu, and press OK to submit it.
The game then compares the guess to the secret code, and marks it with black and gray dots:
filled black dot for each symbol in the correct place;
empty gray circle for each additional correct symbol in the wrong place.
The game doesn't reveal which dots correspond to which symbols, i.e. it only gives a summarized result.
The guess can be repeated as many times as needed until it matches the secret code.
Mouse control:
Click on a symbol in the menu: enters that symbol to the selected field.
Click on a field: selects the field.
Right click on a field: clears the field.
Click on the OK button: submits the guess.
Keyboard control:
Numbers, letters: enter a symbol to the selected field.
Left, Right, Home, End: move the selection.
Delete, Backspace: delete a symbol.
Enter: submits the guess.
Advanced mouse controls:
Right click on a symbol in the menu: disables that symbol, so that it cannot be entered later (until enabled again by a second right click). This can be useful if you deduced that a symbol cannot be in the code.
Double click on a field: fixes the symbol in that field, so that it cannot be deleted later, and it will be automatically inserted in the subsequent guesses (until it is released by a second double click). This can be useful if you deduced that the symbol must be in that position.
Click on a symbol in an earlier guess: copies that symbol to the current guess in the same position. (Right click and double click are also possible, and they have the same effect as on the current guess.)
Advanced keyboard controls:
X: fixes the symbol in the current field (like double click).