Nonogram

Overview

Count the clues along the left edge and the top, and a picture starts to emerge from the blank grid. Nonograms (sometimes called Picross or Hanjie) hand you a 10×10 grid and a list of numbers for every row and column; each number describes a consecutive run of filled cells in that line, in order, separated by at least one blank cell. A row labelled "3 2" means somewhere along it sit a block of three filled cells and then a block of two, with a gap between them. The puzzle is pure cross-referencing: a run that has to live in a particular column because the rows will not fit it anywhere else, and vice versa, until the picture resolves itself. This collection ships ten hand-crafted 10×10 puzzles, with row and column clue highlighting to keep your place and an over-fill warning that turns clues red when you have marked too many cells in a line. A hint system, a timer, and a validate button round out the tools, so you can confirm a finished image rather than guess at it.

How to Play

Left-click fills a cell; right-click marks an X to record that the cell is definitely empty. Click and drag along a row to fill a whole run in one stroke, which is far faster than clicking each cell individually. On a touchscreen, a tap fills and a long-press drops an X marker. The clue numbers beside each row and above each column light up as you complete the corresponding line, and any line you have over-filled turns its clues red as a warning. The validate button checks your current grid against the solution, and the hint button fills or marks a single correct cell when you are stuck.

Tips & Strategy

Begin with the lines that are nearly full. On a 10-wide grid, a clue of "10" fills the entire row, and a clue of "8" can only sit in one of three positions — the cells in the middle of those possibilities are guaranteed filled no matter which position the block actually takes. Mark those certain cells and propagate: each cell you commit tightens the constraints on the crossing column. Use X markers aggressively for cells you have proven empty, because negative information is just as load-bearing as positive. Watch the over-fill red-clue warning closely, since a single mistaken fill cascades into wrong deductions down the line. When two interpretations of a line remain, look at the crossing lines to see which one the columns can support. Cross-hatching small certain blocks first usually exposes enough of the picture that the rest resolves by recognition. Lean on the timer as a pace-setter rather than a score.