Slitherlink· Advanced

Goal

Draw a single closed loop on the dot grid.

Rules

  • Numbers in cells indicate how many edges around that cell are part of the loop.
  • The loop cannot cross or branch. Each dot connects to 0 or 2 line segments.
  • Empty cells (no number) have no constraints.
32321323

Tip

  • Start with 0 and 3 clues — they determine the most edges.
  • Look for diagonal 3-3 patterns and corner number patterns.

Visuospatial reasoning training promotes prefrontal activation and enhances mathematical thinking in children.

  • Lin, Y. et al. (2021). Spatial cognition training in 17,000 children. Nature Scientific Reports.