How to solve Kakuro
Kakuro is a crossword made of sums. Find the clues that can only be made one way, then let the crossing runs narrow each cell down.
How it works
A Kakuro grid has white cells and clue cells. Each line of white cells across or down is a run. The sum clue just before a run, above the slash for across and below it for down, is the total of its digits.
Fill every white cell with a digit from 1 to 9. The digits in a run add up to its clue, and no digit repeats inside a run. A digit can repeat in the grid, just not in the same run.
Most solves start from sums that have only one set of digits, a unique combination. Two cells that make 16 must be 7 and 9, because 8 + 8 repeats. Where an across run and a down run cross, the cell has to fit both.
Where to look first
Short runs with very small or very large clues. Two cells: 3, 4, 16 and 17 have one set each. Three cells: 6, 7, 23 and 24. The table in unique combinations has the rest.
Then look where those runs cross. A cell in two known sets can only hold a digit that is in both.
When nothing is unique
List the sets a run could use and cross out the ones that don’t fit. A set is out when one of its digits has no cell in the run that can hold it. That is elimination, and it is how the weekend grids fall.
Use notes. The runs panel beside the puzzle lists every set for the selected cell’s runs, and strikes the ones your digits have ruled out.
Worth memorizing
Runs never repeat a digit.
That is why 16 in two cells must be 7 + 9.
Start with sums that have one set of digits.
Two cells: 3, 4, 16, 17. Three cells: 6, 7, 23, 24.
A crossing cell fits both runs.
Its digit is in both sets.
Practice
0 of 4 rightAcross 24 in three cells. Which digits must it use?
Three digits are in. What goes in the ringed cell?
Down 17 in two cells. Which digits does it use?
What goes in the ringed cell?