Clue Grid for beginners: read the clues and finish your first board.
Learn what each clue means, practise the two cell actions, and complete a new fixed seventeen-square puzzle without guessing.
Clue Grid begins with twenty-five unknown squares and numbers beside their rows and columns. Your job is to choose which squares are filled. The numbers describe groups of filled squares; they are not values to type into the board or a count of neighboring squares.
This first lesson uses a small, fixed frame pattern. You will learn the symbols and controls, make a few deductions that follow directly from the rules, and finish one complete board. It is a different position from the game's original teaching example, so load the beginner example before following the coordinates below.
Read a clue as a list of consecutive runs
A run is a group of filled squares with no empty square between them. A row clue of 2 1 means a run of two, followed by a later run of one. At least one empty square must separate the runs. Read rows from left to right and columns from top to bottom. There can be extra empty squares before, after, or between the runs, if space permits.
■ ■ · ■ · clue: 2 1 ■ · ■ ■ · clue: 1 2
Both examples contain three filled squares. Their clues differ because the order and grouping differ. The dot in these printed examples means an empty square. On the live board, a blank square means you have not decided yet; an × is your note that it should be empty. Neither blank nor × counts as filled.
Each square belongs to one row and one column. Filling a row correctly is not enough if it breaks a column clue. The completed pattern must satisfy both directions at the same time.
Load the first-board example
Choose Practice this example in the side panel, or Load beginner example below the game. It replaces the current puzzle with an unknown board and sets Edits to zero. Rows R1–R5 run from top to bottom; columns C1–C5 run from left to right. Check the printed clues before playing:
Rows Columns R1: 5 C1: 5 R2: 1 1 C2: 1 1 R3: 1 1 1 C3: 1 1 1 R4: 1 1 C4: 1 1 R5: 5 C5: 5
If your clues differ, you are looking at another puzzle. New puzzle generates a different arrangement; it is not the control for restarting this lesson. Load beginner example brings this exact set back.
Try the cell actions before solving
Fill square places a ■ in the selected cell. Mark empty writes ×. Selecting a cell with the same action again clears that mark; selecting it with the other action replaces the mark. A click changes only that cell, not its neighbors.
- Choose Mark empty and select R2C2. It shows ×.
- Choose Fill square and select R2C2 again. The fill replaces the ×; the square has not been used twice.
- Choose Undo last edit. The previous × returns, and Edits drops from two to one.
- Choose Retry this board. All cells become unknown, Edits returns to zero, and Fill square is selected again. The clues stay unchanged.
That was a control experiment. Do it before your actual attempt so the count and the marks start clean. Undo restores one earlier cell state; Retry clears the whole attempt. The game does not judge whether your × note was logically justified.
With a keyboard, Tab to the action choices and use their normal radio-button controls. Tab to a board cell, then press Enter or Space to apply the selected action. The arrow keys move focus to an adjacent board cell without wrapping across an edge. Cell labels name the row, column, and current mark; the associated descriptions give its row and column clues.
Fill the four lines that have no spare space
Each line contains five squares. A clue of 5 can fit only by filling all five. Row 1 and row 5 therefore fill completely. Column 1 and column 5 do too. When two of these lines meet, their shared corner is still one square.
From a clean attempt, select the following coordinates once each, in this order. The list names the additional side squares after the top and bottom rows, so it never asks you to click a filled corner twice:
- Row 1: C1, C2, C3, C4, C5.
- Row 5: C1, C2, C3, C4, C5.
- Row 2: C1, C5.
- Row 3: C1, C5.
- Row 4: C1, C5.
You have filled sixteen distinct squares. The four sides occupy 5 + 5 + 3 + 3 = 16 squares because the corners must not be counted twice. Edits is sixteen if you made just these fills after Retry. The game is still unfinished: the center remains to be decided.
■ ■ ■ ■ ■ ■ ? ? ? ■ ■ ? ? ? ■ ■ ? ? ? ■ ■ ■ ■ ■ ■
Read the middle row literally
Row 3 has clue 1 1 1: three separate one-square runs. Three fills plus two mandatory separating empty squares already occupy all five positions. Its only arrangement is fill, empty, fill, empty, fill.
R3C1 and R3C5 are already filled by the sides. Fill R3C3. The completed pattern now has seventeen filled squares. Row 2 and row 4 have only their two isolated end squares, matching 1 1. Columns 2 and 4 likewise have only their top and bottom squares. Column 3 has three isolated fills at rows 1, 3, and 5. Every clue agrees.
Reveal the complete beginner board
■ ■ ■ ■ ■ ■ · · · ■ ■ · ■ · ■ ■ · · · ■ ■ ■ ■ ■ ■
The eight dots are empty squares. You may leave those live cells blank or use × notes before the last fill; the empty notes are optional. Filling the sixteen border squares and then the center from a clean attempt wins in seventeen edits.
When the last required fill is placed, the game reports completion and locks the cells. Keyboard focus moves to Undo last edit. Undo reopens the previous position so you can inspect the final choice; Retry clears the attempt and keeps the same clues. Do not expect to keep writing empty notes on a finished board without first undoing or retrying.
Know what a line check can tell you
Check lines compares the runs of your currently filled squares with the row and column clues. It does not grade each cell or confirm your empty notes. On another board, a row can have its correct run lengths in several different positions, and some of those positions may conflict with the columns.
This beginner board avoids that uncertainty: the four full lines force the frame, and the middle row's three isolated runs force the center. That explains its unique answer rather than merely showing a pattern to copy. A random board may require additional deductions; these seventeen coordinates are not a solution to another puzzle.
Why does filling a corner twice undo part of the frame?
With Fill square selected, the second activation clears an existing fill. The top-left corner belongs to both row 1 and column 1, but it is one cell. Use the listed sixteen distinct border coordinates, or inspect each shared corner before activating it again.
Keep the next attempt reproducible
Load beginner example always restores this frame puzzle. Retry restores whichever puzzle you most recently loaded or generated. New puzzle removes the fixed-practice selection and generates another uniquely solvable board. Refreshing a beginner practice entry reloads its example; an ordinary random page starts a new puzzle. Marks, undo history, and Edits are not saved when you leave or refresh.
Edits records your current actions, with Undo stepping that history back. It is not a skill grade or a promise about the fewest deductions. For this lesson, a useful goal is to explain each filled line and the required gaps before selecting the cells.