Where are the naked singles in Sudoku?

The easiest way to find naked singles in the grid is using pencilmarks. Cells with a single pencilmark are easy to spot. Without pencilmarks, you need to inspect the peers of the cell and see if there is only a single digit missing in the peers.

What is the trick to solve Sudoku fast?

Sudoku techniques

1. Scanning in one direction:
2. Scanning in two directions:
3. Searching for Single Candidates:
4. Eliminating numbers from rows, columns and boxes:
5. Searching for missing numbers in rows and columns:
6. Eliminating squares using Naked Pairs in a box:
7. Eliminating squares using Naked Pairs in rows and columns:

How do you solve Sudoku in 1 minute?

Yet there are still 5 tips to solve sudoku puzzles reasonably fast:

1. Scan quickly for single candidates – yes, it is still the easiest and most reliable way to eliminate the unknown from the board.
2. Don’t get stuck for too long on one part of the grid, see rule number 1 and scan the whole board.

What does hidden single mean in Sudoku?

A Hidden Single is a single candidate remaining for a specific digit in a row, column or box. In Sudoku variants, additional constraints can also produce Hidden Singles. An alternative term is Pinned Digit.

What is a naked number in Sudoku?

In sudoku, a naked pair is a set of exactly two candidates that are in exactly two squares in a row, column, or block. For example: In this example, the 2 and 3 in red on the right side is a naked pair. One of the squares in the pair has to be 2, and one of the squares in the pair has to be 3.

What is a fish in Sudoku?

Introducing Boxes Nowadays, any single-digit pattern that compares 2 partially overlapping constraint sets of equal size is called a fish. In standard Sudoku, the sets can contain rows, columns, and boxes. In Sudoku Variations with additional constraints, any combination is possible.