public void GenerateCandidateValues()
{
var values = new[] { 1, 9, 5, 6, 2, 7, 3, 8, 4,
8, 7, 6, 4, 9, 3, 2, 1, 5,
4, 3, 2, 5, 1, 8, 7, 9, 6,
6, 2, 9, 3, 5, 1, 8, 4, 7,
3, 1, 4, 8, 7, 6, 9, 5, 2,
7, 5, 8, 9, 4, 2, 1, 6, 3,
2, 4, 7, 1, 6, 9, 5, 3, 8,
9, 6, 3, 7, 8, 5, 0, 0, 0,
5, 8, 1, 2, 3, 4, 0, 0, 0 };
var cells = GenerateCellGrid(values);
var grid = new SudokuGrid(cells);
grid.GenerateCandidateValues();
grid.GetCandidateValues(7, 6).Count.ShouldBe(1);
grid.GetCandidateValues(7, 7).Count.ShouldBe(1);
grid.GetCandidateValues(7, 8).Count.ShouldBe(1);
grid.GetCandidateValues(8, 6).Count.ShouldBe(1);
grid.GetCandidateValues(8, 7).Count.ShouldBe(1);
grid.GetCandidateValues(8, 8).Count.ShouldBe(1);
}