The construction of the Sudoku puzzle is done in a variety of ways. In most cases, a “puzzle generator” will be used. It is generally thought that Dell uses a computer program to generate their puzzles. A Dell Sudoku puzzle will typically have over 30 “givens” which will be placed in random cells around the grid. Many of these “givens” will lead to the deduction of other obvious number placements. Dell, and other puzzle creators in North America, seldom give any authoring credit to the Sudoku puzzles which they create.
Japanese creators of the Sudoku puzzle are always credited for their work. And most Japanese puzzles are created by hand. Another difference between the American Sudoku and the Japanese Sudoku is that Japanese puzzle creators generally place the “givens” in a symmetrical pattern. As a side note, the “givens” can be placed symmetrically on the grid by allotting a number to them and by deciding ahead of time where they will be placed.
When constructing Sudoku puzzles it is often possible to set each starting grid so that it has more than one solution and to set others so that there is no solution at all. These puzzles are not considered to be a true Sudoku puzzle. This is because when it comes to the general basis of Sudoku, a unique solution is always expected.
Creators of the Sudoku puzzle need to make sure that when they are constructing a grid that they understand where numbers can be logically placed. To overlook the final solution of the puzzle can lead to a grid that is unsolvable and which contradicts the basic premise of what Sudoki is all about.
When you are solving a Sudoku puzzle, and you place a digit randomly to the grid, you are one step closer to the solution but perhaps no closer to the right solution. You can randomly remove one digit and replace it with another but the logic behind the Sudoku puzzle is that you take the time to apply logic and mathematical reasoning.
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