Let's break down the basic Sudoku solving strategies that will help both beginners and professionals. In the instructions below, we'll share working techniques on how to solve the puzzles quickly and easily.
Search for "Hanging Low Fruit."
The strategy is based on picking the numbers needed to place into the squares on the grid by the method of elimination. The player looks at what values are already on the field and then decides to add new ones after that.
Look at the square in the middle row (left column). The numbers 4, 6, 2, 3, 8, 5, 1 and 7 have already been placed here. Naturally, by the method of elimination we realise that there is a nine missing here. When we have inserted the number 9, we can move further in the direction of solving the problem.
But let's see where else we have "low-hanging fruit". We recommend paying attention to the row that runs through the centre row. It, too, is missing just one digit! There are 3, 8, 5, 7, 2, 6, 4 and 9. By the method of elimination we realise that we need one. So we put it in the empty cell.
The Fruit search strategy has yielded results. Now we have a sudoku grid with +2 cells filled.
Explore neighbouring squares
After adding 9 and 1, we see that there is no more such freebies with low fruit. Okay, let's try to move on. The attention is drawn to the middle column of the square in the centre. Sudoku authors have already filled it: 1, 2, 4, 5, 7 and 8. By the method of elimination we realise that we are missing numbers 3, 6 and 9. But how to place them correctly?
To answer the question, we move on. We see neighbouring squares in the left part and at the bottom. We start from the fact that we need to write the values 3, 6 and 9. There is already a six in the square on the left, and at the bottom we see a three. Thus, on the top right in the middle square we need to write a nine. Such an approach is called the method of elimination. It is used not only in everyday life, but also at international championships.
Let's move on and try to find where to "attach" the 3 and 6. The square on the left side already contains a six in the top row, so we reject the possibility of placing a 6 in the top row of the centre square. The method of elimination suggests that only a 3 can be inserted here.
The completed sudoku grid looks like this:
Naturally, for the example we took easy Sudoku, in which the authors have already filled almost all the fields. But the "hanging fruit" strategy can be applied to complex sudoku as well. Just look for obvious solutions and squares / columns / lines with filled cells.