How to play
- Goal
- Place one straight three-cell bar over every circle and join all bars in one closed chain.
- How it ends
- The chart is solved when every bar contains exactly one circle, touches exactly two other bars and belongs to the same loop; mistakes can always be undone.
- Record
- Your fastest first-solve time is kept for each chart, and completed charts remain available for Practice.
- Every bar is straight and exactly three cells long. It contains exactly one circle; cover every circle once. Bars cannot overlap.
- Each bar must share a cell edge with exactly two distinct other bars. Several shared edges with the same bar count once. Corner touches do not connect. All bars belong to one loop; separate cycles are invalid.
- Choose Horizontal and tap the leftmost cell, or Vertical and tap the top cell. A whole bar appears when you release. Erase removes it from any covered cell. Empty cells need no marks.
- Undo and Redo correct placements. More opens Restart, How to play and Settings. The first-solve clock starts on deal and keeps running through Restart and reload.
Controls
| Mouse / touch | Choose a tool, tap the bar’s first cell and release |
|---|---|
| Arrows + Enter / Space | Move and place the selected bar |
| H / V / E | Horizontal / Vertical / Erase |
| Z / Y / R | Undo / Redo / Restart confirmation |
| Escape | Cancel a draft, close a dialog or return to the atlas |
| Controller | D-pad moves; A places; X cycles tools; Y focuses the grid; shoulders Undo/Redo; B returns; Start settings. |
Tips for Irupu
- Start near corners List the straight three-cell bars that can cover a circle without including another circle.
- Use existing bars Overlapping candidates are impossible. One placed bar can force the next circle’s orientation.
- Count bars, not edges A long shared edge still creates one neighbour. A third distinct neighbour is invalid.
- Close the chain Every bar needs two neighbours, and the whole group must connect. Separate small loops cannot finish.
Questions about this game
Must I fill the grid?
No. Empty cells need no marks.
Does a corner contact count?
No. Bars must share a cell edge.
Can I choose which contacts count?
No. Every edge contact counts; a third distinct neighbour is invalid.
Do several shared edges count several times?
No. The same neighbouring bar is counted once.
Can Replay replace my first time?
No. Replay is Practice and retains your first result.
Irupu is a puzzle by Naoki Inaba. These charts and examples are original. Reload keeps marks and Undo; resumed first solves stay local. Shelves describe dimensions, not difficulty.
Watch how to play
About Irupu
Place whole three-cell bars around printed circles, then close one chain through every bar. Gold contact dots and neighbour counts show how the chain fits together.
All 96 original charts are open: twelve 4×4, twenty-four 5×5, twenty-four 6×5 and thirty-six 6×6. Each has exactly one independently verified full-bar ending.
