Nonogram (also known as "Paint By Numbers", "Griddler", "CrossPix", "Hanjie") is a type of puzzles where it is necessary to draw the picture in accordance with the numbers to the left of the rows and on top of the columns. The picture is made up of filled squares and blank (white) squares. The numbers indicate how many groups of filled or colored squares are contained in each row or column, and how many uninterrupted colored squares each group contains. The nonogram puzzle was invented by Non Ishida in 1987, in Japan, therefore in some countries (for example, in Russia) it is called "Japanese Crossword".