Masyu, also known by its alternative names "Shiroshinju Kuroshinju", "White Pearls and Black Pearls", is a logic puzzle that involves creating a continuous, non-intersecting loop through a rectangular grid. The grid contains squares, some of which feature circles that are either "white" (empty) or "black" (filled). The loop must navigate through all circled cells, adhering to specific rules regarding movement through and around these circles.
- Single Continuous Loop: The player must draw a single, continuous loop that does not intersect itself.
- Pass Through Circles: The loop must pass through all circled cells, entering and exiting from the center of one of its four sides.
- 90-Degree Turns: All turns made by the loop must be at 90 degrees.
- White Circles: The loop must go straight through white circles but must turn either immediately before or after it.
- Black Circles: The loop must turn upon the black circles but go straight through the cells immediately before and after them.
Basic Solving Tips
- Start with Certainties: Begin by identifying parts of the loop that are certain, such as turns around black circles that are close to the edge or each other.
- Use the Grid: Utilize the grid to ensure that the loop adheres to the rules regarding turns and straight paths through white and black circles, respectively.
- Avoid Closed Loops: Be cautious not to create smaller, closed loops when navigating through the grid.
- Black Circle Clusters: Pay attention to clusters of black circles, as they often dictate a specific path to avoid breaking the basic rules.