Puzzle guide
How to solve Straights
Straights is a number grid with black cells in it. Every row and column uses each number at most once, and every run of white cells between the black cells holds a straight: numbers that follow on without a gap, in any order. Here is how those two rules work together.
The rules
- Fill every white cell with a number from 1 up to the size of the puzzle. Black cells stay as they are.
- No number appears twice in a row or a column. The numbers in black cells count too.
- Every run of white cells, side by side or one above the other between black cells and edges, holds a straight: numbers that follow on from each other, in any order, like 4 2 3.
- Black cells are never filled in. Some of them show a number.
A solved puzzle
Your first moves
- Look at the black cells with numbers: their number cannot appear anywhere else in that row or column.
- Find short runs next to a known number: a run of two with a 5 holds a 4 or a 6.
- Fill a cell when its row and column leave only one number.
- For every run, ask which straights still fit, and strike out numbers that are too far away.
Techniques, step by step
The last number left
This row has a black 4, and the white cells already hold 2 and 3. A number may appear only once in a row, and the black cell's 4 counts. So the last cell is a 1. Remember: the numbers in black cells count for the no-repeat rule, even though they are not part of any run.
A run is a straight
This run of three white cells holds a 1 and a 3. Its numbers must follow on without a gap, so the middle one can only be a 2. Every run is like this: no gaps, no repeats, in any order.
The range check
A run of two cells next to a 5 can only hold 4 and 5, or 5 and 6. So the empty cell is a 4 or a 6, and everything else is crossed out. In the same way, a run of three cells can never reach further than two steps from any number in it. This check is the move that makes Straights its own puzzle.
What a run must hold
This run of four shows a 3 and a 6. A straight without gaps that holds both of them must also hold 4 and 5, and with four cells there is no room for anything else. So the two empty cells are 4 and 5, in some order. If only one of them can take the 4 because of its column, that decides both.
Pairs in a row
If two cells in the same row can only hold the same two numbers, those numbers are used up for the whole row, across all its runs. Cross them out of every other cell in the row. Three cells sharing three numbers work the same way. The harder boards need this once the run checks stop helping.
Common mistakes
- Forgetting the black cells' numbers. A number in a black cell blocks that number for its whole row and column.
- Treating a whole row as one straight. Each run between black cells is its own straight. A row can hold several.
- Requiring an order. A straight may be in any order: 3 1 2 is fine.
- Using every number in a row. A row with black cells holds fewer numbers than the puzzle's size, so a number can be missing from a row.
Questions and answers
Ready to play?
Use the black cells' numbers, keep every run a straight, and check how far each run can reach. That is how a Straights grid falls into order.