Jigsaw sandwich sudoku

Jigsaw Sudoku is a variation of Sudoku that uses irregular-shaped regions instead of the standard 3x3 blocks. The rules of Jigsaw Sudoku are the same as regular Sudoku, with the following additional rule:

• Each region must contain the numbers 1 to 9, without repetitions.

This means that the puzzle may have a different number of regions than a regular Sudoku puzzle, and the regions may be of different sizes and shapes.

Sandwich Sudoku contains extra numbers outside the grid. These extra clues indicate the sum of digits between 1 and 9 in the corresponding row or column.