ABC

Fill board with letters A, B and C in a way, that the same letters can't contact by side.
Numbers at the top and left on the board shows how many A, B, C letters are in columns and rows.

Online solving: When you click on any field of board, you will see the menu with following options to choose: “-“ – symbol of cancelation, “X” – symbol indicating absence of a letter, “A, B or C” – letters, which will be placed in field. When you choose a wrong letter, the report ‘Wrong solution” will appear. Moreover, when you click on letters presented outside the diagram, you will “unmark” them (it means that particular group of letters are completed). You can also use the option “Hint” or "Clear" from Helper.