Drag the lines to place them; use the slider to rotate.
Each value of n keeps its own point set and progress.
Saving applies only to Four equal regions on this device.
Clear the point set and history for n = 6? Other values of n, settings, and puzzles are kept.
Divide 4n points into four regions with exactly n points in each. A, B, C, and D match the colours in the counts above the field.
Drag a line to slide it; drag the crossing to move both. Use the rotation slider to turn the lines. The crossing also responds to arrow keys; hold Shift for larger steps.
Lines start perpendicular and rotate together. Turn off Keep lines perpendicular in Settings to rotate the solid and dashed lines separately. They stay at least 12° apart.
A point is counted by its centre. A centre on a line is unassigned until the line moves clear. All four counts must match, with no point on a line, to complete the puzzle.
Reset returns the lines to their starting arrangement for these points. Shuffle creates a new solvable point set. Both preserve settings and can be undone. The field turns green when you find an equal split.