Sutoreto ("Sutoretokurosu", "Straight Cross") is a logic puzzle created by Naoki Inaba (Japan). It is played on a rectangular or square grid with black and white cells. Some white cells contain numbers. The aim is to place a number into every white cell. The numbers in a horizontal or vertical stripe of consecutive white cells must form a sequence of numbers without gaps, but in any order (for example: 2-4-1-3).