# Nanro

## Rules[edit]

Label some cells with numbers to form a single connected group of labeled cells; no 2×2 group of cells may be fully labeled. Each bold region must contain at least one labeled cell. Each number, including any given number, must equal the total number of labeled cells in that region. For two labeled cells touching by a side across a thick boundary, the numbers must be different.

(Rules and example from WPC 2017 IB)

## History of the puzzle[edit]

First appeared on *Nikoli* volume 92 (2000). Invented by にょろっぴぃ ("nyoroppyi"), which is an alias of Yuki Kawabe. Original title ナンロー is a contraction of ナンバーロード ("Number Road").

## Variants[edit]

### Nanro Signpost[edit]

Invented by Prasanna Seshadri (India) in 2016. His first puzzle can be seen on GM Puzzles.

Label some cells with numbers to form a single connected group of labeled cells. No 2×2 group of cells may be fully labeled. Each number must be equal to the total number of labeled cells in that bold region, and all bold regions contain at least one labeled cell. The given numbers indicate how many cells are labeled in that region, but not necessarily which cells are labeled. For two labeled cells touching by a side across a thick boundary, the numbers must be different.

(Rules and example from WPC 2017 IB)

## Appearances in the past WPCs[edit]

- WPC 2019/World Cup Round 1 by Roland Voigt
- WPC 2019/Round 11 (Cairo Pentagonal Signpost) by Ulrich Voigt
- WPC 2017/Round 4 (Signpost) by Prasanna Seshadri
- WPC 2017/Round 7 (Signpost) by Prasanna Seshadri
- WPC 2017/Round 12 by Prasanna Seshadri
- WPC 2017/Round 22 by Prasanna Seshadri
- WPC 2013/Part 5