The illustration of the nine-square grid method is as follows:
"Nine-square grid" is a boundary grid used for copywriting in the history of Chinese calligraphy. It is also called "nine-square grid"; it also refers to a type of mobile phone keyboard. The layout is relative to the full keyboard. "Jiugongge" is also a very popular game.
There are two essences of problem solving: Hidden Single and Naked Single. Their names are named based on the candidate number method.
There are two problem-solving methods developed based on the nature of problem-solving:
Elimination method
Elimination method: use numbers to find the only fillable blank in the unit , is called the elimination method, and the number that can fill in the unique blank is called the elimination solution (implicit unique solution).
According to different scopes of action, hidden solutions can be divided into the following three types:
1.1 Numbers can fill in unique blanks in the "Palace" unit, which is called hidden solution (Hidden) Single in Box), this solution is called palace elimination method.
1.2 The number that can fill in the only blank space in the "row" unit is called Hidden Single in Row. This solution is called the Hidden Single in Row method.
1.3 Numbers that can fill in unique spaces in the "column" unit are called Hidden Single in Column. This solution is called the column elimination method.
1.4 Hidden Single in Line solution and Hidden Single in Line solution are collectively called Hidden Single in Line solution.
1.5 The method of obtaining the row-rank elimination solution is called the row-rank elimination method.