16 char Sudoku

+ _ + - _ 9
9 4 - - _ 1 7 _
- 7 _ - _ 8 -
+ _ + _ -
- _ + 5 _ -
- - 6 9 _ - _
_ + _ - -
- 3 8 5 2 - -
_ 6 _ 1 _ + _ _

Liang's 16 character Sudoku Definition and Game Rules:
1 circle number (plus sign), this box is a non couple number. The upper and lower boxes in the same column, as well as the left and right boxes in the same row, both have upper and lower (left and right) squares (cross or T-shaped structure, a total of five nine squares) with two pairs of couple numbers in the same row (column). There are three pairs in the same row and three pairs in the same column.
Two deletion line numbers (minus sign), the other two numbers on the left (right) side of the same palace row, are called row couple numbers, both of which exist in the left (right) two palaces. There are also a pair of couple numbers in the same row, for a total of three pairs.
The three underlined numbers and the other two numbers in the column above (below) where the same palace is located are called column couple numbers, both of which have a pair of couple numbers in the same column in the upper (lower) two palaces. There are a total of three pairs.
4 ordinary numbers, unmarked, not belonging to the numbers defined and described by 1, 2, and 3. Belonging to the 'couple numbers'.